Vinyl polymers and processes for producing the same

ABSTRACT

The present invention relates to a method for producing a vinyl polymer retaining the ability for atom transfer radical polymerization, a method for reliably producing a vinyl polymer having terminal functional groups, a vinyl polymer having functional groups prepared by these methods, and a curable composition comprising the polymer. A vinyl polymer having terminal functional groups can be reliably produced through the steps of preparing a vinyl polymer by atom transfer radical polymerization of a vinyl monomer in a polymerization solvent in the presence of a polymerization initiator and a transition metal complex functioning as a polymerization catalyst, removing the polymerization solvent and the vinyl monomer while the ability for atom transfer radical polymerization is maintained, and supplying a functional-group-introducing agent having a low polymerizability to introduce a functional group to a polymer terminus. During the step of supplying the functional-group-introducing agent, a functional-group-introducing solvent having a dielectric constant higher than that of the functional-group-introducing agent may be supplied to effectively introduce a functional group to a terminus of the vinyl polymer. Furthermore, according to the present invention, the polymerization solvent and the functional-group-introducing agent can be recovered and recycled.

TECHNICAL FIELD

The present invention relates to a method for producing a vinyl polymerhaving functional groups introduced therein, a vinyl polymer havingfunctional groups introduced therein made by this method, and a curablecomposition containing the polymer.

BACKGROUND ART

It is a well-known fact that functional-group-terminated polymers aloneor in combination with suitable curing agents can provide cured productshaving high heat resistance and high durability by crosslinking.Representative examples of such polymers are polymers having alkenylgroups, hydroxy groups, or crosslinkable silyl groups at the termini.

Alkenyl-terminated polymers can be crosslinked by photoreaction or inthe presence of hydrosilyl-containing compounds functioning as curingagents. Hydroxyl-terminated polymers are cured by the formation ofurethane crosslinks resulting from the reaction with polyisocyanates.Polymers having crosslinkable silyl groups at the termini are cured byabsorption of moisture in the presence of suitable condensationcatalysts.

Main chain skeletons of the polymers having alkenyl groups, hydroxylgroups, or crosslinkable silyl groups at the termini consist of, forexample, polymers prepared by ionic polymerization or condensationpolymerization. Examples of such main chain polymers include polyetherpolymers such as polyethylene oxide, polypropylene oxide, andpolytetramethylene oxide; hydrocarbon polymers such as polybutadiene,polyisoprene, polychloroprene, polyisobutylene, and hydrogenatedproducts thereof; and polyester polymers such as polyethyleneterephthalate, polybutylene terephthalate, and polycaprolactone. Thesepolymers are used in various applications depending on the main chainstructure and the type of crosslinks. On the other hand, vinyl polymersprepared by radical polymerization and having functional groups at thetermini are not currently put to practical application.

Among vinyl polymers, (meth)acrylic polymers have particularly highweather resistance and high transparency, neither of which can beachieved by polyether polymers, hydrocarbon polymers, or polyesterpolymers. Thus, (meth)acrylic polymers having alkenyl groups orcrosslinkable silyl groups in the side chains are applied toweather-resistant paints and the like. Vinyl polymers having alkenylgroups or crosslinkable silyl groups at the termini instead of in theside chain can provide cured products having superior physicalproperties. Thus, many researchers have investigated simplified methodsfor producing vinyl polymers having terminal functional groups.

However, in the preparation of vinyl polymers, inhibition of the sidereaction is difficult; thus, polymers having a target molecular weightand a uniform molecular weight distribution cannot be readily produced.Moreover, introduction of functional groups to specific positions isparticularly difficult. Methods for industrially producing vinylpolymers having terminal functional groups have not been reported sofar.

For example, Japanese Unexamined Patent Application Publication No.5-255415 teaches a method for producing a (meth)acrylic polymer havingalkenyl groups at both termini by the reaction with analkenyl-containing disulfide functioning as a chain transfer agent.Japanese Unexamined Patent Application Publication No. 5-262808 teachesa method for producing a (meth)acrylic polymer, including the steps ofpreparing a (meth)acrylic polymer having hydroxyl groups at both terminiby the reaction with a hydroxyl-containing disulfide, and introducingthe alkenyl groups into both termini by utilizing the reactivity of thehydroxyl groups. However, reliable introduction of alkenyl groups intothe both termini is not easy according to these methods. In order toreliably introduce functional groups to both termini, a large quantityof a chain transfer agent must be used, and this poses a problem in themanufacturing process.

Furthermore, the present inventors have discovered a method forintroducing a functional group into a terminus of a polymer, includingthe step of polymerizing a vinyl polymer by the living radicalpolymerization described below; adding a compound containing afunctional group and an alkenyl group having a low polymerizability, thecompound functioning as an agent for introducing the functional group;and allowing the alkenyl group to react with a terminus of the polymer.

However, this method also has a possibility of not being able toreliably introduce only one functional group into a terminus of thepolymer. This is attributable to the following two reasons: One is adecrease in catalytic activity. Depending on the type and/or thequantity of the agent for introducing the functional group, the polarityof the system may change as a result of the addition of the agent,thereby decreasing the catalytic activity. The other is the introductionof a plurality of functional groups due to the presence of the monomerduring the step of introducing the functional group. During the step ofadding the functional-group-introducing agent, the polymerizable monomeris preferably absent; however, at the end stage of the polymerization,the reaction becomes gradually slower, and trace amounts ofpolymerizable monomers remain as a result. When the polymerizablemonomers are present during the step of adding thefunctional-group-introducing agent, it is sometimes difficult to controlthe number of functional groups introduced into one end. After thereaction between the radically propagating terminus and thefunctional-group-introducing agent, the terminus (having the functionalgroup) normally has low radical reaction activity; thus, it is lesslikely that the terminus will further react with another molecule of thefunctional-group-introducing agent. However, when a polymerizablemonomer is present in the reaction system during the reaction betweenthe radically propagating terminus and the functional-group-introducingagent, it is possible that the polymerizable monomer having highpolymerizability will react with this terminus of the polymer. Once thepolymerizable monomer is added to the terminus, the terminus regainshigh activity and starts to react with another molecule of thefunctional-group-introducing agent. A plurality of molecules of thefunctional-group-introducing agent will be introduced in the polymer asa result of the addition of the polymerizable monomer to the terminusand the reaction with the new molecule of thefunctional-group-introducing agent after the reaction between theradically propagating terminus and the functional-group-introducingagent. When this occurs, it becomes more difficult to introduce onemolecule of the functional-group-introducing agent into one terminus ofthe polymer.

In order to control the rate of introduction of the functional group,the amount of remaining monomer at the end stage of the polymerizationmay be analyzed so that the functional-group-introducing agent canalways be fed at a constant degree of polymerization. However, thisrequires a complicated process analysis step. According to an approachthat does not conduct process analysis, a significantly long time isrequired before the degree of polymerization reaches a steady state.

When a compound having two alkenyl groups having a low polymerizabilityis used as the functional-group-introducing agent and the feed amount ofthe agent is equal to or less than the number of the active termini,both functional groups may react, thereby coupling two polymer termini.In order to reliably introduce the functional groups into the twotermini of the polymer, the agent must be charged in an amount largerthan that of the propagating termini. In some cases, it is preferable toadd an excessive amount of the functional-group-introducing agent inorder to increase the reaction rate and to reliably introduce thefunctional group into the termini. The excessfunctional-group-introducing agent is recovered after the introductionof the functional group by a process such as distillation under areduced pressure. These compounds are preferably recycled. Inparticular, when the functional-group-introducing agent is expensive,recycling of these compounds is particularly important in themanufacturing process.

When a polymerization solvent is used in the polymerization of the vinylpolymer, the polymerization solvent is recovered with thefunctional-group-introducing agent during the step of recovering thefunctional-group-introducing agent by reduced-pressure distillation. Thepolymerization solvent containing the functional-group-introducing agentcannot be recycled as a polymerization solvent since functional groupsare introduced into the main chain before a predetermined molecularweight is reached. In order to recycle the solvent as a polymerizationsolvent, the polymerization solvent must be isolated from thefunctional-group-introducing agent.

Two or more compounds can be isolated from each other by varioustechniques, e.g., crystallization and adsorption. Among these, adistillation isolation technique is popular. According to thistechnique, two or more compounds are isolated from each other based onthe difference in boiling point. The isolation is highly difficult whenthe difference between the boiling points of the compounds is small orwhen an azeotropic composition is contained. In other words, when thedifference between the boiling point of the polymerization solvent andthe boiling point of the functional-group-introducing agent is small orwhen an azeotropic composition is contained, the polymerization solventand the functional-group-introducing agent can rarely be isolated fromeach other and thus cannot be recycled as a polymerization solvent and afunctional-group-introducing agent, respectively. This poses a problemin the manufacturing process. For example, although 1,7-octadiene (afunctional-group-introducing agent) and acetonitrile (a polymerizationsolvent) have a difference in boiling point of at least 30° C., thepresent inventors have found that they also contain an azeotropiccomposition. In such a system, the two components cannot be isolatedfrom each other unless special distillation, such as azeotropicdistillation requiring the addition of a third component, is conducted.Furthermore, it is highly difficult to find a suitable third component.

As is described above, the following must be considered in order toreliably introduce one functional group into one terminus of thepolymer: a decrease in catalytic activity due to thefunctional-group-introducing agent; recovery of thefunctional-group-introducing agent and isolation of the agent from thepolymerization solvent; and the timing of addition of thefunctional-group-introducing agent at a particular degree ofpolymerization in order to reliably achieve a constant rate ofintroduction of the functional group.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a polymer having afunctional group at a terminus and a predetermined molecular weight, amethod for producing the polymer, and a curable composition containingthe polymer. Another object of the present invention is to provide amethod for efficiently producing the polymer at low cost by respectivelyrecovering the polymerization solvent and thefunctional-group-introducing agent at high purities to allow recycling.

The present invention relates to a method for making a vinyl polymerhaving a terminus to which a functional-group-introducing agent isadded. The method includes a step of supplying thefunctional-group-introducing agent having a low polymerizability and afunctional-group-introducing solvent having a dielectric constant higherthan that of the functional-group-introducing agent to a polymerizationsystem after 80 percent by weight or more of a vinyl monomer is consumedby atom transfer radical polymerization in a polymerization solvent inthe presence of a polymerization initiator and a transition metalcomplex functioning as a polymerization catalyst. In this method, 1 to1,000 parts by weight of the functional-group-introducing solvent to 100parts by weight of the vinyl monomer is supplied.

In the above-described method, the polymerization solvent and the vinylmonomer are preferably removed by reduced-pressure distillation whilethe ability for atom radical transfer polymerization is maintained after80 percent by weight or more of the vinyl monomer is consumed.

More preferably, after the polymerization solvent and the vinyl monomerare removed by reduced-pressure distillation, thefunctional-group-introducing agent is supplied to introduce a functionalgroup.

After the functional-group-introducing agent is supplied to introducethe functional group, the functional-group-introducing agent or amixture of the functional-group-introducing agent and thefunctional-group-introducing solvent is preferably removed byreduced-pressure distillation.

The present invention also relates to a polymer produced by theabove-described production method.

The present invention also relates to a curable composition containingthe above-described polymer.

BEST MODE FOR CARRYING OUT THE INVENTION

In the present invention, atom transfer radical polymerization of avinyl monomer is conducted in a polymerization solvent in the presenceof a polymerization initiator and a transition metal complex functioningas a polymerization catalyst. After the consumption of 80 percent byweight of the vinyl monomer, an agent for introducing a functional group(a functional-group-introducing agent) having a low polymerizability anda solvent for introducing the functional group(functional-group-introducing solvent) are fed to produce a vinylpolymer in which a molecule of the functional-group-introducing agent isadded to each terminus. The functional-group-introducing solvent has ahigher dielectric constant than that of the functional-group-introducingagent and is supplied in an amount of 1 to 1,000 parts by weight to 100parts by weight of the vinyl monomer.

Controlling radical polymerization is generally difficult due to a highpolymerization rate and frequent terminations of the reaction resultingfrom radical coupling. On the other hand, living radical polymerizationyields less frequent termination of the reaction and can producepolymers having a narrow molecular weight distribution, i.e., Mw/Mn of1.1 to 1.5. Moreover, the molecular weight can be freely controlled byadjusting the feed ratio of the initiator to the monomer. Thus,according to the living radical polymerization, not only polymers havinga narrow molecular weight distribution and a low viscosity can beproduced, but also monomers having specific functional groups can bereliably introduced into predetermined positions in almost all cases.Living radical polymerization is thus preferred as a method forproducing vinyl polymers having particular functional groups.

The term “living polymerization” in a strict sense refers to apolymerization process in which the propagating termini remain activethrough the propagation of the molecular chain. In a general (broad)sense, the term includes quasiliving polymerization in which propagationproceeds with equilibrium between active and inactive chains. In thepresent invention the term “living polymerization” is used in the lattersense.

Living radical polymerization has been extensively investigated byvarious study groups. Examples include a process using a cobaltporphyrin complex disclosed in J. Am. Chem. Soc., 1994, vol. 116, p.7943; a process using a radical scavenger such as a nitroxide radicaldisclosed in Macromolecules, 1994, vol. 27, p. 7288; and atom transferradical polymerization (ATRP) using an organohalide compound or the likeas an initiator and a transition metal complex as a catalyst.

Among various living radical polymerization processes, an ATRP processfor polymerizing a vinyl monomer catalyzed by a transition metal complexin the presence of an organohalide compound, a halogenated sulfonylcompound, or the like functioning as an initiator is particularlypreferred as the method for producing a vinyl polymer having a specificfunctional group. This is due to the fact that the ATRP process not onlyhas the advantages of the living radical polymerization, but also allowsgreater flexibility in designing the initiator or the catalyst since thepolymer has a halogen group or the like contributing to the functionalgroup conversion at an end.

Examples of the ATRP processes are disclosed in Matyjaszewski et al., J.Am. Chem. Soc. 1995, vol. 117, p. 5614; Macromolecules, 1995, vol. 28,p. 7901; Science, 1996, vol. 272, p. 866; WO 96/30421; WO 97/18247; andSawamoto et al., Macromolecules, 1995, vol. 28, p. 1721.

The vinyl monomer used in the production of the vinyl polymer is notparticularly limited as long as it is radically polymerizable. Variousvinyl monomers may be used.

Examples of the vinyl monomer include (meth)acrylic monomers. Examplesof the (meth)acrylic monomers include (meth)acrylic acid and alkylesters (the number of carbon atoms in the alkyl group: 1 to 50) of(meth)acrylic acid such as methyl(meth)acrylate, ethyl(meth)acrylate,n-propyl(meth)acrylate, isopropyl(meth)acrylate, n-butyl(meth)acrylate,isobutyl(meth)acrylate, tert-butyl(meth)acrylate,n-pentyl(meth)acrylate, n-hexyl(meth)acrylate, cyclohexyl(meth)acrylate,n-heptyl(meth)acrylate, n-octyl(meth)acrylate,2-ethylhexyl(meth)acrylate, n-nonyl(meth)acrylate,n-decyl(meth)acrylate, n-dodecyl(meth)acrylate, andn-stearyl(meth)acrylate; cyclic alkyl esters (the number of carbon atomsin the cyclic alkyl group: 5 to 50) of (meth)acrylic acid such ascyclohexyl(meth)acrylate; isobornyl esters of (meth)acrylic acid such asisobornyl(meth)acrylate; aryl esters of (meth)acrylic acid (the numberof carbon atoms in the aryl group: 6 to 50) of (meth)acrylic acid, suchas phenyl(meth)acrylate and toluyl(meth)acrylate; aralkyl esters (thenumber of carbon atoms in the aralkyl group: 7 to 50) of (meth)acrylicacid such as benzyl(meth)acrylate; alkoxyalkyl esters (the number ofcarbon atoms in the alkoxy group: 1 to 50, the number of carbon atoms inthe alkyl group: 1 to 50) of (meth)acrylic acid, such as2-methoxyethyl(meth)acrylate, 2-ethoxyethyl(meth)acrylate, and3-methoxybutyl(meth)acrylate; hydroxyalkyl esters (the number of carbonatoms in the alkyl group: 1 to 50) of (meth)acrylic acid, such as2-hydroxyethyl(meth)acrylate and 2-hydroxypropyl(meth)acrylate;epoxy-containing alkyl esters (the number of carbon atoms in the alkylgroup: 1 to 50) of (meth)acrylic acid, such as glycidyl(meth)acrylate;aminoalkyl esters (the number of carbon atoms in the alkyl group: 1 to50) of (meth)acrylic acid, such as 2-aminoethyl(meth)acrylate;alkoxysilyl-containing alkyl esters (the number of carbon atoms in thealkoxy group: 1 to 50, the number of carbon atoms in the alkyl group: 1to 50) of (meth)acrylic acid, such asγ-(methacryloyloxypropyl)trimethoxysilane; ethylene oxide adducts (thenumber of ethylene oxide adducts: 2 to 50) of (meth)acrylic acid; andfluorine-containing alkyl esters (the number of carbon atoms in thefluorine-containing alkyl group: 1 to 50) of (meth)acrylic acid such astrifluoromethylmethyl(meth)acrylate,2-trifluoromethylethyl(meth)acrylate,2-perfluoroethylethyl(meth)acrylate,2-perfluoroethyl-2-perfluorobutylethyl(meth)acrylate,2-perfluoroethyl(meth)acrylate, perfluoromethyl(meth)acrylate,diperfluoromethylmethyl(meth)acrylate,2-perfluoromethyl-2-perfluoroethylmethyl(meth)acrylate,2-perfluorohexylethyl(meth)acrylate,2-perfluorodecylethyl(meth)acrylate, and2-perfluorohexadecylethyl(meth)acrylate. Examples of the vinyl monomerfurther include styrenic monomers such as styrene, vinyltoluene,α-methylstyrene, chlorostyrene, styrenesulfonic acid, and salts thereof;fluorine-containing vinyl monomers such as perfluoroethylene,perfluoropropylene and vinylidene fluoride; silicon-containing vinylmonomers, e.g., vinylalkoxysilanes such as vinyltrimethoxysilane andvinyltriethoxysilane; maleic anhydride, maleic acid, and monoalkylesters and dialkyl esters of maleic acid; fumaric acid, and monoalkylesters and dialkyl esters of fumaric acid; maleimide monomers such asmaleimide, methylmaleimide, ethylmaleimide, propylmaleimide,butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide,stearylmaleimide, phenylmaleimide, and cyclohexylmaleimide;nitrile-containing vinyl monomers such as acrylonitrile andmethacrylonitrile; amido-containing vinyl monomers such as acrylamideand methacrylamide; vinyl esters such as vinyl acetate, vinylpropionate, vinyl pivalate, vinyl benzoate, and vinyl cinnamate; alkenessuch as ethylene and propylene; conjugated dienes such as butadiene andisoprene; and vinyl chloride, vinylidene chloride, allyl chloride, andallyl alcohol. These monomers may be used alone or in combination. Amongthese monomers, styrenic monomers and (meth)acrylic monomers arepreferred from the standpoint of the physical properties of theresulting product. Acrylic ester monomers and in particular butylacrylate are preferred for their low glass transition temperatures andhigh reactivity in introducing the functional group.

Examples of the polymerization initiator include organohalide compounds,in particular, organohalide compounds having a highly reactivecarbon-halogen bond (for example, an ester compound having a halogenatom in the a position and a compound having a halogen atom in thebenzylic position); and sulfonyl halide compounds.

Examples of the organohalide compounds include C₆H₅—CH₂X, C₆H₅—CHX—CH₃,and C₆H₅—C(X)(CH₃)₂ (wherein X represents a chlorine atom, a bromineatom, or an iodine atom); and R⁷—CHX—CO₂R⁸, R⁷—CX(CH₃)—CO₂R⁸,R⁷—CHX—C(O)R⁸, and R⁷—CX(CH₃)—C(O)R⁸ (wherein R⁷ and R⁸ are each ahydrogen atom, a C₁-C₂₀ alkyl group, a C₆-C₂₀ aryl group, or a C₇-C₂₀aralkyl group; and X represents a chlorine atom, a bromine atom, or aniodine atom).

Examples of the sulfonyl halide compounds used as the polymerizationinitiator include R⁷—C₆H₄—SO₂X (wherein R⁷ is a hydrogen atom, a C₁-C₂₀alkyl group, a C₆-C₂₀ aryl group, or a C₇-C₂₀ aralkyl group; and Xrepresents a chlorine atom, a bromine atom, or an iodine atom).

When atoms transfer radical polymerization of the vinyl monomer isperformed in the presence of the organohalide compound or the sulfonylhalide compound functioning as an initiator, a vinyl polymer having aterminal structure represented by formula (6) is produced as a result:—CX(R⁹)(R¹⁰)  (6)(wherein R⁹ and R¹⁰ each represent a group bonded to an ethylenicallyunsaturated group of the vinyl monomer, and X represents a chlorineatom, a bromine atom, or an iodine atom).

Alternatively, the ATRP initiator may be an organohalide compound or asulfonyl halide compound having both a functional group that initiatesthe polymerization and a specific reactive functional group that doesnot initiate the polymerization. In such a case, the produced vinylpolymer has the specific reactive functional group introduced into oneterminus of the main chain while the structure represented by formula(6) is introduced into the other terminus of the main chain.

Examples of the specific reactive functional group include alkenyl,crosslinkable silyl, hydroxyl, epoxy, amino, and amide. Since thesegroups are highly reactive, another suitable functional group can beintroduced into the vinyl polymer in one or more reaction steps.

The organohalide compound having the alkenyl group is not particularlylimited. Examples thereof include the compounds represented by thegeneral formula (7):R¹²R¹³CX—R¹⁴—R¹⁵—C(R¹¹)═CH₂  (7)(wherein R¹¹ represents a hydrogen atom or a methyl group; R¹² and R¹³each represent a hydrogen atom, a C₁-C₂₀ alkyl group, a C₆-C₂₀ arylgroup, or a C₇-C₂₀ aralkyl group, and may be coupled to each other atfree termini; R¹⁴ represents —COO— (ester), —CO— (keto), or o-, m-, orp-phenylene; R¹⁵ represents a direct bond or a C₁-C₂₀ divalent organicgroup which may include at least one ether bond; and X represents achlorine atom, a bromine atom, or an iodine atom).

Examples of R¹² and R¹³ include a hydrogen atom, methyl, ethyl,n-propyl, isopropyl, butyl, pentyl, and hexyl. R¹² and R¹³ may bond witheach other at the other termini to form a cyclic skeleton.

Examples of R¹⁵ include a direct bond and C₁-C₂₀ divalent organicgroups, each of which may include at least one ether bond. Examples ofthe C₁-C₂₀ alkylene group include —(CH₂)_(n)—, wherein n represents aninteger between 1 and 20. Examples of the group containing at least oneether bond include —O—(CH₂)—, —(CH₂)_(n)—O—, —(CH₂)_(n)—O—(CH₂)_(m)—,wherein 1≦m+n≦20).

Examples of the alkenyl-containing organohalide compound represented bygeneral formula (7) include:

-   XCH₂COO(CH₂)_(n)CH═CH₂,-   CH₃CHX—COO(CH₂)CH═CH₂,-   (CH₃)₂CX—COO(CH₂)_(n)CH═CH₂,-   CH₃CH₂CHX—COO(CH₂)CH═CH₂,    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; and n represents an integer between 1 to 20),-   XCH₂COO(CH₂)_(n)O(CH₂)_(m)CH═CH₂,-   CH₃CHX—COO(CH₂)_(n)O(CH₂)_(m)CH═CH₂,-   (CH₃)₂CX—COO(CH₂)_(n)O(CH₂)_(m)CH═CH₂,-   CH₃CH₂CHX—COO(CH₂)_(n)O(CH₂)_(m)CH═CH₂,    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; m represents an integer between 0 to 19; n represents an    integer between 1 and 20; and 1≦m+n≦20),-   o, m, p-XCH₂—C₆H₄—(CH₂)_(n)—CH═CH₂,-   o, m, p-CH₃CHX—C₆H₄—(CH₂)_(n)—CH═CH₂,-   o, m, p-CH₃CH₂CHX—C₆H₄—(CH₂)_(n)—CH═CH₂    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; and n represents an integer between 1 to 20),-   o, m, p-XCH₂—C₆H₄—(CH₂)_(n)—O—(CH₂)_(m)—CH═CH₂,-   o, m, p-CH₃CHX—C₆H₄—(CH₂)_(n)—O—(CH₂)_(m)—CH═CH₂,-   o, m, p-CH₃CH₂CHX—C₆H₄—(CH₂)_(n)—O—(CH₂)_(m)CH═CH₂    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; m represents an integer between 0 to 19; n represents an    integer between 1 to 20; and 1≦m+n≦20),-   o, m, p-XCH₂—C₆H₄—O—(CH₂)_(n)—CH═CH₂,-   o, m, p-CH₃CHX—C₆H₄—O— (CH₂)_(n)—CH═CH₂,-   o, m, p-CH₃CH₂CHX—C₆H₄—O— (CH₂)_(n)—CH═CH₂,    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; and n represents an integer between 1 to 20; and 1≦m+n≦20),-   o, m, p-XCH₂—C₆H₄—O—(CH₂)_(n)—O—(CH₂)_(m)—CH═CH₂,-   o, m, p-CH₃CHX—C₆H₄—O—(CH₂)_(n)—O—(CH₂)_(m)—CH═CH₂, and-   o, m, p-CH₃CH₂CHX—C₆H₄—O—(CH₂)_(n)—O—(CH₂)_(m)—CH═CH₂    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; m represents an integer between 0 and 19; n represents an    integer between 1 and 20; and 1≦m+n≦20).

Examples of the alkenyl-containing organohalide compound includecompounds represented by general formula (8):CH₂═C(R¹¹)—R¹⁵—CX(R¹²)—R¹⁶—R¹³  (8)(wherein R¹¹, R¹², R¹³, R¹⁵, and X are the same as above; and R¹⁶ is adirect bond, —COO— (ester), —CO— (keto), or o-, m-, or p-phenylene).

R¹⁵ is a direct bond or a C₁-C₂₀ divalent organic group (which mayinclude at least one ether bond). When R¹⁵ is a direct bond, the vinylgroup bonds to the carbon atom bonding to the halogen atom, therebyproducing an allyl halide compound. Since the carbon-halogen bond isactivated by the presence of the vinyl group adjacent to the halogenatom, R¹⁶ needs not be —COO— or a phenylene group but may be a directbond. When R¹⁵ is other than the direct bond, R¹⁶ is preferably —COO—,—CO—, or phenylene to activate the carbon-halogen bond.

Examples of the compounds represented by general formula (8) include:

-   CH₂═CHCH₂X, CH₂═C(CH₃)CH₂X,-   CH₂═CHCHX—CH₃, CH₂═C(CH₃)CHX—CH₃,-   CH₂═CHCX(CH₃)₂, CH₂═CHCHX—C₂H₅,-   CH₂═CHCHX—CH(CH₃)₂, CH₂═CHCHX—C₆H₅,-   CH₂═CHCHX—CH₂C₆H₅, CH₂═CHCH₂CHX—CO₂R,-   CH₂═CH(CH₂)₂CHX—CO₂R,-   CH₂═CH(CH₂)₃CHX—CO₂R,-   CH₂═CH(CH₂)₈CHX—CO₂R, CH₂═CHCH₂CHX—C₆H₅,-   CH₂═CH(CH₂)₂CHX—C₆H₅, and-   CH₂═CH(CH₂)₃CHX—C₆H₅    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; R represents a C₁-C₂₀ alkyl group, a C₆-C₂₀ aryl group, or a    C₇-C₂₀ aralkyl group).

Examples of the alkenyl-containing sulfonyl halide compound include:

-   o-, m-, p-CH₂═CH—(CH₂)_(n)—C₆H₄—SO₂X and-   o-, m-, p-CH₂═CH—(CH₂)_(n)—O—C₆H₄—SO₂X, wherein X represents a    chlorine atom, a bromine atom, or an iodine atom; and n represents    an integer between 1 and 20.

The organohalide compound containing crosslinkable silyl is notparticularly limited. Examples thereof are compounds represented bygeneral formula (9):R¹²R¹³CX—R¹⁴—R¹⁵—CH(R¹¹)—CH₂—[Si(R¹⁷)_(2-b)(Y)_(b)O]_(m)—Si(R¹⁸)_(3-a)(Y)_(a)  (9)(wherein R¹¹, R¹², R¹³, R¹⁴, R¹⁵, and X are the same as above; R¹⁷ andR¹⁸ each represent a C₁-C₂₀ alkyl group, a C₆-C₂₀ aryl group, a C₇-C₂₀aralkyl group, or a triorganosiloxy group represented by (R′)₃SiO—(wherein R′s are each a C₁-C₂₀ monovalent hydrocarbon group, and thethree R′s may be the same or different); when two or more R¹⁷s or R¹⁸sare present, they may be the same or different; Y represents a hydroxylgroup or a hydrolyzable group; when two or more Ys are present, they maybe the same or different; a represents 0, 1, 2, or 3; b represents 0, 1,or 2; m represents an integer between 0 and 19; and a+mb≧1).

Examples of the compounds represented by general formula (9) include:

-   XCH₂COO(CH₂)_(n)Si(OCH₃)₃,-   CH₃CHX—COO(CH₂)_(n)Si(OCH₃)₃,-   (CH₃)₂CX—COO(CH₂)_(n)Si(OCH₃)₃,-   XCH₂COO(CH₂)_(n)Si(CH₃)(OCH₃)₂,-   CH₃CHX—COO(CH₂)_(n)Si(CH₃)(OCH₃)₂, and-   (CH₃)₂CX—COO(CH₂)_(n)Si(CH₃)(OCH₃)₂ (wherein X represents a chlorine    atom, a bromine atom, or an iodine atom; and n represents an integer    between 0 and 20);-   XCH₂COO(CH₂)_(n)O(CH₂)_(m)Si (OCH₃)₃,-   H₃CCHX—COO(CH₂)_(n)O(CH₂)_(m)Si(OCH₃)₃,-   (H₃C)₂CX—COO(CH₂)_(n)O(CH₂)_(m)Si(OCH₃)₃,-   CH₃CH₂CHX—COO(CH₂)_(n)O(CH₂)_(m)Si(OCH₃)₃,-   XCH₂COO(CH₂)_(n)O(CH₂)_(m)Si(CH₃)(OCH₃)₂,-   H₃CCHX—COO(CH₂)_(n)O(CH₂)_(m)Si(CH₃)(OCH₃)₂,-   (H₃C)₂CX—COO(CH₂)_(n)O(CH₂)_(m)Si(CH₃)(OCH₃)₂, and-   CH₃CH₂CHX—COO(CH₂)_(n)O(CH₂)_(m)Si(CH₃)(OCH₃)₂    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; m represents an integer between 0 to 20; and n represents an    integer between 1 and 20); and-   o, m, p-XCH₂—C₆H₄—(CH₂)₂Si(OCH₃)₃,-   o, m, p-CH₃CHX—C₆H₄—(CH₂)₂Si(OCH₃)₃,-   o, m, p-CH₃CH₂CHX—C₆H₄—(CH₂)₂Si(OCH₃)₃,-   o, m, p-XCH₂—C₆H₄—(CH₂)₃Si(OCH₃)₃,-   o, m, p-CH₃CHX—C₆H₄—(CH₂)₃Si(OCH₃)₃-   o, m, p-CH₃CH₂CHX—C₆H₄—(CH₂)₃Si(OCH₃)₃-   o, m, p-XCH₂—C₆H₄—(CH₂)₂—O—(CH₂)₃Si(OCH₃)₃,-   o, m, p-CH₃CHX—C₆H₄—(CH₂)₂—O—(CH₂)₃Si(OCH₃)₃,-   o, m, p-CH₃CH₂CHX—C₆H₄—(CH₂)₂—O—(CH₂)₃Si(OCH₃)₃,-   o, m, p-XCH₂—C₆H₄—O—(CH₂)₃Si(OCH₃)₃,-   o, m, p-CH₃CHX—C₆H₄—O—(CH₂)₃Si(OCH₃)₃,-   o, m, p-CH₃CH₂CHX—C₆H₄—O—(CH₂)₃Si(OCH₃)₃,-   o, m, p-XCH₂—C₆H₄—O—(CH₂)₂—O—(CH₂)₃—Si(OCH₃)₃,-   o, m, p-CH₃CHX—C₆H₄—O—(CH₂)₂—O—(CH₂)₃—Si(OCH₃)₃, and-   o, m, p-CH₃CH₂CHX—C₆H₄—O—(CH₂)₂—O—(CH₂)₃—Si(OCH₃)₃    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom).

Examples of the organohalide compound containing crosslinkable silylfurther include compounds represented by general formula (10):(R¹⁸)_(3-a)(Y)_(a)Si—[OSi(R¹⁷)_(2-b)(Y)_(b)]_(m)—CH₂—CH(R¹¹)—R¹⁵—CX(R¹²)—R¹⁶—R¹³  (10)(wherein R¹¹, R¹², R¹³, R¹⁵, R¹⁶, R¹⁷, R¹⁸, a, b, m, X, and Y are thesame as above).

Examples of such compounds include:

-   (CH₃O)₃SiCH₂CH₂CHX—C₆H₅,-   (CH₃O)₂(CH₃)SiCH₂CH₂CHX—C₆H₅,-   (CH₃O)₃Si(CH₂)₂CHX—CO₂R,-   (CH₃O)₂(CH₃)Si(CH₂)₂CHX—CO₂R,-   (CH₃O)₃Si (CH₂)₃CHX—CO₂R,-   (CH₃O)₂(CH₃)Si (CH₂)₃CHX—CO₂R,-   (CH₃O)₃Si(CH₂)₄CHX—CO₂R,-   (CH₃O)₂(CH₃)Si(CH₂)₄CHX—CO₂R,-   (CH₃O)₃Si(CH₂)₉CHX—CO₂R,-   (CH₃O)₂(CH₃)Si(CH₂)₉CHX—CO₂R,-   (CH₃O)₃Si(CH₂)₃CHX—C₆H₅,-   (CH₃O)₂(CH₃)Si(CH₂)₃CHX—C₆H₅,-   (CH₃O)₃Si(CH₂)₄CHX—C₆H₅, and-   (CH₃O)₂(CH₃)Si(CH₂)₄CHX—C₆H₅    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; and R represents a C₁-C₂₀ alkyl group, a C₆-C₂₀ aryl group, or    a C₇-C₂₀ aralkyl group).

The organohalide compound or sulfonyl halide compound containing ahydroxyl group may be any. Examples thereof include compoundsrepresented byHO—(CH₂)_(n)—O—CO—CHX(R)(wherein X represents a chlorine atom, a bromine atom, or an iodineatom; R represents a hydrogen atom, a C₁-C₂₀ alkyl group, a C₆-C₂₀ arylgroup, or a C₇-C₂₀ aralkyl group; and n represents an integer between 1and 20).

The organohalide compound or sulfonyl halide compound containing anamino group may be any. Examples thereof include compounds representedbyH₂N—(CH₂)_(n)—OCO—CHX(R)(wherein X represents a chlorine atom, a bromine atom, or an iodineatom; R represents a hydrogen atom, a C₁-C₂₀ alkyl group, a C₆-C₂₀ arylgroup, or a C₇-C₂₀ aralkyl group; and n represents an integer between 1and 20).

The organohalide compound or sulfonyl halide compound containing anepoxy group may be any. Examples thereof include compounds representedby

(wherein X represents a chlorine atom, a bromine atom, or an iodineatom; R represents a hydrogen atom, a C₁-C₂₀ alkyl group, a C₆-C₂₀ arylgroup, or a C₇-C₂₀ aralkyl group; and n represents an integer between 1and 20).

In order to prepare a polymer having two or more reactive functionalgroups per molecule, it is preferable to use a polyfunctionalorganohalide or sulfonyl halide polymerization initiator having two ormore initiation sites.

Examples of the polymerization initiator include

-   o, m, p-X—CH₂—C₆H₄—CH₂—X    (wherein C₆H₄ represents a phenylene group; and X represents a    chlorine atom, a bromine atom, or an iodine atom)    (wherein R represents a C₁-C₂₀ alkyl group, a C₆-C₂₀ aryl group, or    a C₇-C₂₀ aralkyl group; n represents an integer between 0 and 20;    and X represents a chlorine atom, a bromine atom, or an iodine atom)    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; and n represents an integer between 0 and 20)    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom; and n represents an integer between 1 and 20)    o, m, p-X—SO₂—C₆H₄—SO₂—X    (wherein X represents a chlorine atom, a bromine atom, or an iodine    atom).

Examples of the transition metal complex that functions as thepolymerization catalyst include metal complexes having Groups VII, VIII,IX, X, and XI elements as the central metals. Metal complexes havingGroup VIII, IX, X, or XI metals as the central metals are preferred.

Examples of the central metals include iron, nickel, ruthenium, andcopper. Monovalent copper, divalent ruthenium, and divalent iron arepreferred, and copper is particularly preferred.

Examples of the metal compound that gives the metal transition complex(i.e., the compound before the ligand coordination) include cuprouschloride, cuprous bromide, cuprous iodide, cuprous cyanide, cuprousoxide, cuprous acetate, and cuprous perchlorate.

Examples of the ligand that coordinates to the metal compound for thetransition metal complex include 2,2′-bipyridyl and its derivatives;1,10-phenanthroline and its derivatives; alkylamines such as tributylamine; polyamines such as tetramethylethylenediamine,pentamethyldiethylenetriamine, hexamethyltriethylenetetraamine, andtris(2-dimethylaminoethyl)amine; and triphenylphosphine. These ligandsmay be used alone or in combination. Polyamines and triamines arepreferred from the standpoint of reaction control.

When a copper compound is used as the metal compound for the transitionmetal complex, a ligand for promoting the catalytic activity isgenerally supplied to produce a transition metal complex. Examples ofthe ligand include 2,2′-bipyridyl and its derivatives;1,10-phenanthroline and its derivatives; alkylamines such as tributylamine; and polyamines such as tetramethylethylenediamine,pentamethyldiethylenetriamine, hexamethyltriethylenetetraamine, andtris(2-dimethylaminoethyl)amine.

When divalent ruthenium chloride is used as the metal compound for thetransition metal complex, a ligand, such as triphenylphosphine, isgenerally used to produce a transition metal complex, such as atris(triphenylphosphine) complex (RuCl₂(PPh₃)₃).

When the tris(triphenylphosphine) complex (RuCl₂(PPh₃)₃) is used, it ispreferable to add an aluminum compound, such as trialkoxyaluminum, toincrease its activity.

When divalent iron chloride is used as the metal compound for thetransition metal complex, a ligand, such as triphenylphosphine, isgenerally supplied to produce a transition metal complex, such as atris(triphenylphosphine) complex (FeCl₂(PPh₃)₃).

The polymerization may be conducted without any solvent or with varioussolvents. The polymerization may be conducted in an emulsion system, asuspension system, or a system mediated by supercritical fluid CO₂.

Examples of the polymerization solvent include hydrocarbon solvents suchas benzene and toluene; ether solvents such as diethylether andtetrahydrofuran; halogenated hydrocarbon solvents such as methylenechloride and chloroform; ketonic solvents, such as acetone, methyl ethylketone, and methyl isobutyl ketone; alcohol solvents such as methanol,ethanol, propanol, isopropanol, n-butyl alcohol, and tert-butyl alcohol;nitrile solvents such as acetonitrile, propionitrile, and benzonitrile;ester solvents such as ethyl acetate and butyl acetate; and carbonatesolvents such as ethylene carbonate and propylene carbonate. These maybe used alone or in combination. Nitrile solvents and in particularacetonitrile are preferred since they improve the catalytic stability.

In the present invention, the vinyl polymer is produced by atom transferradical polymerization of a vinyl monomer in the presence of apolymerization initiator and a transition metal complex catalyst in apolymerization solvent.

Since this polymerization is living polymerization, it is possible toproduce a block copolymer by successively feeding vinyl monomers.

The content of the polymerization solvent used is preferably adjusted toachieve sufficient dissolution or dispersion of the catalyst in thepolymerization system. In particular, the polymerization solvent contentis 0.1 to 300 parts, preferably 1 to 100 parts, and more preferably 5 to30 parts to 100 parts of the vinyl monomer.

The above-described amounts of the polymerization solvent, thepolymerization initiator, and the transition metal complex catalyst arecharged in a reactor. To these, a vinyl monomer is, for example,supplied dropwise to prepare a vinyl polymer.

The polymerization temperature is preferably in the range of roomtemperature to 200° C., and more preferably in the range of 50 to 150°C. from the standpoint of reaction control.

The vinyl polymer is preferably a (meth)acrylic polymer, more preferablyan acrylic ester polymer, and most preferably a butyl acrylate polymer.

Here, the term “(meth)acrylic polymer” refers to a polymer containing50% or more of the (meth)acrylic monomer unit. The (meth)acrylic polymerpreferably contains 80% or more of the (meth)acrylic monomer unit. The(meth)acrylic polymer contains 50% or less and more preferably 20% orless of other vinyl monomer unit or units.

The term “acrylic ester polymer” refers to a polymer containing 50% ormore of the acrylic ester monomer unit. The acrylic ester polymerpreferably contains 80% or more of the acrylic ester monomer unit. Theacrylic ester polymer contains 50% or less and more preferably 20% orless of other monomer unit or units.

The term “butyl acrylate polymer” refers to a polymer containing 50% ormore of the butyl acrylate unit. The butyl acrylate polymer preferablycontains 80% or more of the butyl acrylate unit. The butyl acrylatepolymer contains 50% or less and more preferably 20% or less of othermonomer unit or units.

In the present invention, a functional-group-introducing agent having alow polymerizability and a functional-group-introducing solvent having ahigher dielectric constant than that of the functional-group-introducingagent are supplied after the consumption of 80 percent by weight of thevinyl monomer to produce a vinyl polymer having afunctional-group-introducing agent at an end.

When the functional-group-introducing agent is supplied before 80percent by weight of the vinyl monomer is consumed, the molecular weightof the vinyl polymer often becomes smaller than the target value.Accordingly, the functional-group-introducing agent is preferablysupplied after 80 to 99.9 percent by weight and more preferably 85 to 99percent by weight of the vinyl monomer is consumed.

In the present invention, the polymerization solvent and the vinylmonomer are preferably removed by reduced-pressure distillation whilethe ability for atom transfer radical polymerization is maintained,after 80 percent by weight of the vinyl monomer is consumed, and beforethe functional-group-introducing agent is fed. After the polymerizationsolvent and the vinyl monomer are removed by reduced-pressuredistillation while the ability for atom transfer radical polymerizationis maintained, the system contains a vinyl polymer having the abilityfor atom transfer radical polymerization and is substantially free ofthe residual monomer. Thus, when the functional-group-introducing agentis supplied, a vinyl polymer having a terminal group introduced to aterminus can be produced. Accordingly, it becomes possible to avoid theproblems that has conventionally occurred by the addition of thefunctional-group-introducing agent in the presence of the residualmonomers, i.e., the problem of difficulty of controlling the terminalstructure and the number of functional groups introduced into oneterminus due to the occurrence of random copolymerization resulting fromthe addition of a highly polymerizable monomer to an active terminushaving a functional group. Moreover, it is no longer necessary toconduct a complicated step analysis in which the content of the residualmonomer is analyzed at the end stage of the polymerization in order toalways add the functional-group-introducing agent at a particular degreeof polymerization. A problem of taking a long time before the degree ofpolymerization becomes steady can also be overcome.

The temperature during the reduced-pressure distillation is preferably150° C. or less, more preferably 100° C. or less, and most preferably80° C. or less.

The reduced-pressure distillation may be conducted by atmosphericpressure evaporation or reduced-pressure evaporation. Thereduced-pressure distillation may be conducted subsequent to thepolymerization at the same temperature so that no additional heating isrequired, which is preferable from the standpoint of the manufacturingprocess.

The simplest process for removing the polymerization solvent and thevinyl monomer by reduced-pressure distillation is a batch process.Alternatively, the polymerization solvent and the vinyl monomer may becontinuously removed by reduced-pressure distillation with a thin-layerevaporator or the like.

In order for the vinyl polymer to retain the ability for atom transferradical polymerization after the removal of the polymerization solventand the vinyl monomer, oxygen contamination during the step of removingthe polymerization solvent and the vinyl monomer must be avoided.

The recovered polymerization solvent and the vinyl monomer containsubstantially no foreign components and thus can be reused, eitherdirectly or after a simple process, such as adjustment of the vinylmonomer content, to produce a new vinyl polymer.

Since the removal of the polymerization solvent and the vinyl monomer byvacuum evaporation is conducted before feeding thefunctional-group-introducing agent, the recovered material substantiallycontains only the polymerization solvent and the vinyl monomer. Thus,the purities of the recovered materials after the vacuum evaporation arehigh, and the recovered materials can be efficiently reused in the nextpolymerization.

The functional-group-introducing agent may be selected from thecompounds represented by general formula (1):

{wherein R³ represents a hydroxyl group, an amino group, an epoxy group,a carboxylic acid group, an ester group, an ether group, an amido group,a silyl group, a group represented by general formula (2):

(wherein R⁴ represents a hydrogen atom or a methyl group), or a C₁-C₂₀organic group containing no polymerizable olefin; R¹ represents a C₁-C₂₀alkylene group or a group represented by general formula (3):

(wherein R⁵ is a C₁-C₂₀ organic group which may contain an oxygen atomor a nitrogen atom; and R⁶s each represent a hydrogen atom or a methylgroup and may be the same or different); and R² represents a hydrogenatom or a methyl group}.

The compound having two alkenyl groups having a low polymerizability foruse in introducing alkenyl groups is selected from the compoundsrepresented by general formula (4):

{wherein R¹ represents a C₁-C₂₀ alkylene group or a group represented bygeneral formula (3):

(wherein R⁵ is a C₁-C₂₀ organic group which may contain an oxygen atomor a nitrogen atom; and R⁶s each represent a hydrogen atom or a methylgroup and may be the same or different); and R² and R⁴ each represent ahydrogen atom or a methyl group}.

R² and R⁴ may each represent a hydrogen atom or methyl but arepreferably a hydrogen atom. When R¹ represents a C₁-C₂₀ alkylene, thestructure of the compound is not particularly limited, but may berepresented by general formula (5), for example:

In view of the availability of the starting material, n is preferably 2,4, or 6.

Specific examples of R¹ in general formula (1) include:

-   —(CH₂)_(n)— (wherein n represents an integer between 1 and 20),    —CH(CH₃)—, —CH(CH₂CH₃)—, —C(CH₃)₂—, —C(CH₃) (CH₂CH₃)—, —C(CH₂CH₃)₂—,    —CH₂CH(CH₃)—, —(CH₂)_(n)—O—CH₂— (wherein n represents an integer    between 1 and 19), —CH(CH₃)—O—CH₂—, —CH(CH₂CH₃)—O—CH₂—,    —C(CH₃)₂—O—CH₂—, —C(CH₃)(CH₂CH₃)—O—CH₂—, —C(CH₂CH₃)₂—O—CH₂—,    —(CH₂)_(n)—O—(CH₂)_(m)— (wherein m and n are each an integer between    1 and 19; and 2≦m+n≦20),-   —(CH₂)_(n)—C(O)O—(CH₂)_(m)— (wherein m and n are each an integer    between 1 and 19; and 2≦m+n≦20),-   —(CH₂)_(n)—OC(O)—(CH₂)_(m)—C(O)O—(CH₂)₁— (wherein 1 is an integer    between 0 and 18; m and n are each an integer between 1 and 17; and    2≦1+m+n≦20),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—, —(CH₂)_(n)-o-, m-, p-C₆H₄—(CH₂)_(m)—    (wherein m represents an integer between 0 and 13; n represents an    integer between 1 to 14; and 1≦m+n≦14),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—O—(CH₂)_(m)— (wherein m represents an    integer between 0 and 13; n represents an integer between 1 and 14;    and 1≦m+n≦14),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—O—CH(CH₃)— (wherein n represents an    integer between 1 and 12),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—O—CH(CH₃)₂— (wherein n represents an    integer between 1 and 11),-   —(CH₂)_(n)-o-, m-, P—C₆H₄—C(O)O—(CH₂)_(m)— (wherein m and n are each    an integer between 1 and 12; and 2≦m+n≦13),-   —(CH₂)_(n)—OC(O)-o-, m-, p-C₆H₄—C(O)O—(CH₂)_(m)— (wherein m and n    are each an integer between 1 and 11; and 2≦m+n≦12),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—OC(O)—(CH₂)_(m)— (wherein m and n are each    an integer between 1 and 12; and 2≦m+n≦13), and-   —(CH₂)_(n)—C(O)O-o-, m-, p-C₆H₄—(CH₂)_(m)— (wherein m and n are each    an integer between 1 and 11; and 2≦m+n≦12).

Examples of R³ include the following groups:

(wherein R¹⁹ and R²⁰ each represent a C₁-C₂₀ alkyl group, a C₆-C₂₀ arylgroup, a C₇-C₂₀ aralkyl group, or a triorganosiloxy group represented by(R′)₃SiO— (wherein R′s are each a C₁-C₂₀ monovalent hydrocarbon groupand may be the same or different); when two or more R¹⁹s or R²⁰s arepresent, they may be the same or different; Y represents a hydroxylgroup or a hydrolyzable group; when two or more Ys are present, they maybe the same or different; a represents 0, 1, 2, or 3; b represents 0, 1,or 2; m represents an integer between 0 and 19; a+mb≧1; and R²¹represents a C₁-C₂₀ hydrocarbon group).

Specific examples of R²¹ include the following groups:

-   —(CH₂)_(n)—CH₃,-   —CH(CH₃)—(CH₂)_(n)—CH₃,-   —CH(CH₂CH₃)—(CH₂)_(n)—CH₃,-   —CH(CH₂CH₃)₂,-   —C(CH₃)₂—(CH₂)_(n)—CH₃,-   —C(CH₃)(CH₂CH₃)—(CH₂)—CH₃,-   —C₆H₅,-   —C₆H₅(CH₃),-   —C₆H₄(CH₃)₂,-   —(CH₂)_(n)—C₆H₅,-   —(CH₂)_(n)—C₆H₄(CH₃), and-   —(CH₂)_(n)—C₆H₃(CH₃)₂, (wherein n represents an integer of 0 or    more; and the total number of carbon atoms in each group is 20 or    less).

The silyl group is not particularly limited but preferably has m of 0 inthe above-described formulae.

The compound containing an amino group, a hydroxy group, or a carboxylicacid group may be directly reacted with a terminus of the polymer. Theremay be cases where these groups adversely affect the polymer terminus orthe catalyst. In such cases, a compound with a protective group may beused. Examples of the protective group include an acetyl group, a silylgroup, and an alkoxy group.

As the functional-group-introducing agent, any compound having afunctional group that can be added to the vinyl polymer having theability for atom transfer radical polymerization and a target functionalgroup desired to be introduced into the vinyl polymer can be usedwithout limitation. Specific examples include 1,7-octadiene,1,5-hexadiene, 1,9-decadiene, allyl alcohol, pentenol, and hexenol.1,7-Octadiene, 1,5-hexadiene, and 1,9-decadiene are particularlypreferred in view of the availability of the starting materials and thephysical properties of the resulting polymer and a hardened product ofthe polymer.

The amount of the functional-group-introducing agent is not particularlylimited. Since the functional-group-introducing agent preferablycontains a functional group having a low polymerizability, the amount ispreferably high in order to increase the reaction rate. In order toreduce the cost, the amount is preferably substantially equivalent tothe number of the propagating termini. Thus, the amount of thefunctional-group-introducing agent is preferably adjusted according todemand.

The amount of the functional-group-introducing agent having two or morealkenyl groups having a low polymerizability supplied to introduce thealkenyl groups to the termini is preferably approximately two times ormore larger than that of the propagating termini. When the amount isequal to or less than the amount of the propagating termini, bothalkenyl groups may react to couple the polymerization termini. When thecompound contains two alkenyl groups having the same reactivity,coupling occurs at a particular statistical probability based on theexcess amount of the functional-group-introducing agent. Thus, theamount of the functional-group-introducing agent is preferably at least1.5 times, more preferably at least 3 times, and most preferably atleast 5 times that of the polymerization termini. The upper limit ispreferably 30 times that of the polymerization termini in view ofpolarity of the system.

The alkenyl group represented by general formula (1) and having a doublebond consisting of only hydrogen and carbon atoms is generally known tohave a low radical polymerizability. Such an alkenyl group rarelyinduces radical transfer reaction. Thus, when the polymerization solventand the remaining vinyl monomer are removed and then thefunctional-group-introducing agent is supplied, thefunctional-group-introducing agent reacts with the vinyl polymerretaining the ability for atom transfer radical polymerization. As aresult, substantially one molecule of the functional-group-introducingagent attaches to a terminus of the vinyl polymer, thereby producing apolymer having one functional group at an end.

The reaction between the functional-group-introducing agent and thevinyl polymer having the ability for atom transfer radicalpolymerization proceeds in a living state. The transition metal complexcatalyzes the reaction between the functional-group-introducing agentand the vinyl polymer having the ability for atom transfer radicalpolymerization.

Certain types of functional-group-introducing agent having a lowpolymerizability may decrease the polarity of the reaction system andthe activity of the polymerization catalyst. The polarity of thereaction system and the reactivity can be increased by supplying afunctional-group-introducing solvent having a dielectric constant higherthan that of the functional-group-introducing agent. Examples of thefunctional-group-introducing solvent are not limited to but includehydrocarbon compounds such as benzene and toluene; ether compounds suchas diethylether and tetrahydrofuran; halogenated hydrocarbon compoundssuch as methylene chloride and chloroform; ketonic compounds such asacetone, methyl ethyl ketone, and methyl isobutyl ketone; alcoholcompounds such as methanol, ethanol, propanol, isopropanol, n-butylalcohol, and tert-butyl alcohol; nitrile compounds such as acetonitrile,propionitrile, and benzonitrile; ester compounds such as ethyl acetateand butyl acetate; and carbonate compounds such as ethylene carbonateand propylene carbonate. These solvents may be used alone or incombination. The solvent may be the same as or different from thepolymerization solvent but is preferably the same to facilitate recoveryafter the reaction. The dielectric constant of thefunctional-group-introducing solvent is preferably at least 3 higher,and more preferably at least 5 higher, and most preferably at least 10higher than that of the functional-group-introducing agent. The higherthe dielectric constant of the functional-group-introducing solvent, thelarger the effect of improving the polarity. Herein, the dielectricconstant is the value at 20° C. Among these solvents, nitrile compoundsare preferred, and acetonitrile is more preferred in view of improvingthe catalytic stability.

The content of the functional-group-introducing agent is preferably 1 to1,000 parts by weight (hereinafter, simply “parts”), more preferably 5to 500 parts, and most preferably 10 to 100 parts to 100 parts of thevinyl monomer at the initiation of the reaction. The content of thefunctional-group-introducing solvent is preferably 1 to 10,000 parts,and more preferably 10 to 1,000 parts to 100 parts of thefunctional-group-introducing agent. If the content of the solvent forintroducing the functional group is excessively small, the polarity ofthe system cannot be sufficiently increased. If the content of thesolvent is excessively high, the recovery after the polymerization wouldbe difficult.

The excess functional-group-introducing agent can be recovered, forexample, together with the functional-group-introducing solvent byreduced-pressure distillation and can be reused. This is of a greatindustrial advantage. According to this method including the steps ofproducing a vinyl polymer by atom transfer radical polymerization of avinyl monomer, removing the polymerization solvent and the vinyl monomerby reduced-pressure distillation while the ability for atom transferradical polymerization is maintained, and subsequently supplying thefunctional-group-introducing agent, the functional-group-introducingagent is prevented from becoming mixed with the polymerization solventor unreacting vinyl monomers. Thus, isolation of thefunctional-group-introducing agent from the polymerization solvent orthe unreacted vinyl monomers for the purpose of recycling is no longernecessary. In contrast, according to a conventional technique in whichthe polymerization solvent and the vinyl monomer are not removed byreduced-pressure distillation, the functional-group-introducing agent isrecovered together with the polymerization solvent and the vinylmonomer; thus, an isolation process is necessary.

In the present invention, the excess functional-group-introducing agentand functional-group-introducing solvent are recovered after theintroduction of the functional groups. The recovery is usually done byreduced-pressure distillation. If the heat resistance of the polymer issufficient, the system may be heated to a temperature equal to or higherthan the temperature for functional-group introduction so as to increasethe distillation rate. These compounds may be directly removed byreduced-pressure distillation from the reactor, but continuousdistillation, such as a technique using a thin-layer evaporator, is moreefficient. The functional-group-introducing solvent recovered by thereduced-pressure distillation can be reused as a mixture of thefunctional-group-introducing agent and the functional-group-introducingsolvent for use in the step of functional group introduction. In thismanner, the functional-group-introducing solvent can be recycledseparate from the polymerization solvent. Here, an adequate amount ofthe functional-group-introducing agent may be supplied to the mixture soas to compensate for the loss that occurs during the introduction of thefunctional group.

The terminal structure of the polymer produced by the present inventionis represented by general formula (11). The vinyl polymer having such anterminal structure is characterized in that approximately one functionalgroup is bonded to a polymer terminus directly through a carbon-carbonbond without intervened by any heteroatom.

{wherein R³ represents a hydroxyl group, an amino group, an epoxy group,a carboxylic acid group, an ester group, an ether group, an amido group,a silyl group, a group represented by general formula (2):

(wherein R⁴ represents a hydrogen atom or a methyl group), or a C₁-C₂₀organic group containing no polymerizable olefin; R¹ represents a C₁-C₂₀alkylene group or a group represented by general formula (3):

(wherein R⁵ is a C₁-C₂₀ organic group which may contain an oxygen atomor a nitrogen atom; and R⁶s each represent a hydrogen atom or a methylgroup and may be the same or different); R² represents a hydrogen atomor a methyl group; and X represents a halogen group}.

In general formula (11), specific examples of R¹ include the following:

-   —(CH₂)_(n)— (wherein n is an integer between 1 and 20),-   —CH(CH₃)—, —CH(CH₂CH₃)—, —C(CH₃)₂—,-   —C(CH₃)(CH₂CH₃)—, —C(CH₂CH₃)₂—,-   —CH₂CH(CH₃)—, —(CH₂)_(n)—O—CH₂— (wherein n is an integer between 1    and 19),-   —CH(CH₃)—O—CH₂—, —CH(CH₂CH₃)—O—CH₂—,-   —C(CH₃)₂—O—CH₂—, —C(CH₃) (CH₂CH₃)—O—CH₂—, —C(CH₂CH₃)₂—O—CH₂—,-   —(CH₂)_(n)—O—(CH₂)_(m)— (wherein m and n each represent an integer    between 1 and 19; and 2≦m+n≦20),-   —(CH₂)_(n)—C(O)O—(CH₂)_(m)— (wherein m and n each represent an    integer between 1 and 19; and 2≦m+n≦20),-   —(CH₂)_(n)—OC(O)—(CH₂)_(m)—C(O)O—(CH₂)₁— (wherein 1 represents an    integer between 0 and 18; m and n each represent an integer between    1 and 17; and 2≦1+m+n≦20),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—, —(CH₂)_(n)-o-, m-, p-C₆H₄—(CH₂)_(m)—    (wherein m is an integer between 0 and 13; n is an integer between 1    and 14; and 1≦m+n≦14),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—O—(CH₂)_(m)— (wherein m is an integer    between 0 and 13; n is an integer between 1 and 14; and 1≦m+n≦14),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—O—CH(CH₃)— (wherein n is an integer    between 1 and 12),-   —(CH₂)_(m)-o-, m-, p-C₆H₄—O—CH(CH₃)₂— (wherein n represents an    integer between 1 and 11),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—C(O)O—(CH₂)_(m)— (wherein m and n each    represent an integer between 1 and 12; and 2≦m+n≦13),-   —(CH₂)_(n)—OC(O)-o-, m-, p-C₆H₄—C(O)O—(CH₂)_(m)— (wherein m and n    each represent an integer between 1 and 11; and 2≦m+n≦12),-   —(CH₂)_(n)-o-, m-, p-C₆H₄—OC(O)—(CH₂)_(m)— (wherein m and n each    represent an integer between 1 and 12; and 2≦m+n≦13), and-   —(CH₂)_(n)—C(O)O-o-, m-, p-C₆H₄—(CH₂)_(m)— (wherein m and n each    represent an integer between 1 and 11; and 2≦m+n≦12).

Examples of R³ include the following:

In the above-described formula, R¹⁹ and R²⁰ each represent a C₁-C₂₀alkyl group, a C₆-C₂₀ aryl group, a C₇-C₂₀ aralkyl group, or atriorganosiloxy group represented by (R′)₃SiO— (wherein R′s are each aC₁-C₂₀ monovalent hydrocarbon group, and the three R′s may be the sameor different); when two or more R¹⁹s or R²⁰s are present, they may bethe same or different; Y represents a hydroxyl group or a hydrolyzablegroup; when two or more Ys are present, they may be the same ordifferent; a represents 0, 1, 2, or 3; b represents 0, 1, or 2; mrepresents an integer between 0 and 19; and a+mb≧1.

R²¹ represents a C₁-C₂₀ hydrocarbon group. Examples of R²¹ include thefollowing:

-   —(CH₂)_(n)—CH₃,-   —CH(CH₃)—(CH₂)_(n)—CH₃,-   —CH(CH₂CH₃)—(CH₂)_(n)—CH₃,-   —CH(CH₂CH₃)₂,-   —C(CH₃)₂—(CH₂)_(n)—CH₃,-   —C(CH₃)(CH₂CH₃)—(CH₂)_(n)—CH₃,-   —C₆H₅,-   —C₆H₅(CH₃),-   —C₆H₄(CH₃)₂,-   —(CH₂)_(n)—C₆H₅,-   —(CH₂)_(n)—C₆H₄(CH₃), and-   —(CH₂)_(n)—C₆H₃(CH₃)₂, (wherein n is an integer of 0 or more; and    the total number of carbon atoms in each group is 20 or less).

In general formula (12), R² may be a hydrogen atom or a methyl group butis preferably a hydrogen atom. X is preferably a halogen group and morepreferably a bromo group in view of ease of production.

When an alkenyl group is introduced into a terminus and R¹ is a C₁-C₂₀alkylene group, the structure is not particularly limited. An examplethereof is as follows:

In view of the availability of the starting materials, n is preferably2, 4, or 6.

The number of terminal functional groups per polymer molecule is notparticularly limited. When the polymer is for use in a curablecomposition or the like, the number is preferably 0.5 to 5, morepreferably 1 to 3, and most preferably 1.5 to 2.5.

The polymer produced by the present invention preferably has a molecularweight distribution of less than 1.8, more preferably 1.6 or less, andmost preferably 1.3 or less. The molecular weight distribution here isthe ratio of the weight-average molecular weight to the number-averagemolecular weight determined by gel permeation chromatography.

The number-average molecular weight of the polymer produced in thepresent invention is preferably in the range of 500 to 100,000, and morepreferably 3,000 to 50,000. At a molecular weight of 500 or less, thepolymer cannot exhibit its inherent characteristics. At a molecularweight of 100,000 or more, handling becomes difficult.

The functional group introduced into the polymer made according to thepresent invention may be directly used or may be subjected to anotherconversion reaction to introduce another functional group.

For example, an alkenyl group at a polymer terminus may be convertedinto a crosslinkable silyl group through hydrosilylation with ahydrosilane compound having a crosslinkable silyl group. Anyalkenyl-terminated vinyl polymer prepared by the above-described processmay be used.

The hydrosilane compound is not particularly limited. Representativeexamples include the compounds represented by general formula (12):H—[Si(R²²)_(2-b)(Y)_(b)O]_(m).Si(R²³)_(3-a)(Y)_(a)  (12)(wherein R²² and R²³ each represent a C₁-C₂₀ alkyl group, a C₆-C₂₀ arylgroup, a C₇-C₂₀ aralkyl group, or a triorganosiloxy group represented by(R′)₃SiO— (wherein R′s are each a C₁-C₂₀ monovalent hydrocarbon group,and the three R′s may be the same or different); when two or more R²²sor R²³s are present, they may be the same or different; Y represents ahydroxyl group or a hydrolyzable group; when two or more Ys are present,they may be the same or different; a represents 0, 1, 2, or 3; brepresents 0, 1, or 2; m represents an integer between 0 and 19; anda+mb≧1).

The hydrolyzable group represented by Y is not particularly limited andmay be one known in the art. Examples of the hydrolyzable group includehydrogen, a halogen atom, an alkoxy group, acyloxy group, a ketoximategroup, an amino group, an amido group, an acid amido group, an aminooxygroup, a mercapto group, and an alkenyloxy group. An alkoxy group, whichis mildly hydrolyzable and is easy to handle, is particularly preferred.The number of hydroxyl groups or hydrolyzable groups that can bond toone silicon atom is 1 to 3. Thus, the total number of the hydrolyzablegroup, i.e., a+mb, is preferably in the range of 1 to 5. When two ormore hydrolyzable or hydroxyl groups are bonded in the reactive silicongroup, the hydrolyzable or hydroxy groups may be the same or different.The number of the silicon atom in the crosslinkable silicon compound maybe one or more, and may be about up to 20 when the silicon atoms arebonded through siloxane bonds.

Specific examples of R²² and R²³ in general formula (12) include alkylgroups such as a methyl group and an ethyl group; cycloalkyl groups suchas a cyclohexyl group; aryl groups such as a phenyl group; aralkylgroups such as a benzyl group; and triorganosilyl groups represented by(R′)₃SiO— wherein R's are each a methyl group, a phenyl group, or thelike.

Among the hydrosilane compounds, those having a crosslinkable grouprepresented by general formula (13) are preferred due to their wideavailability:H—Si(R²³)_(3-a)(Y)_(a)  (13)(wherein R²³, Y, and a are the same as above). Examples of thehydrosilane compounds having a crosslinkable group represented bygeneral formula (12) or (13) include the following:

-   HSiCl₃, HSi(CH₃)Cl₂, HSi(CH₃)₂Cl, HSi(OCH₃)₃, HSi(CH₃)(OCH₃)₂,    HSi(CH₃)₂OCH₃, HSi(OC₂H₅)₃, HSi(CH₃)(OC₂H₅)₂, HSi(CH₃)₂OC₂H₅,    HSi(OC₃H₇)₃, HSi(C₂H₅)(OCH₃)₂, HSi(C₂H₅)₂OCH₃, HSi(C₆H₅)(OCH₃)₂,    HSi(C₆H₅)₂(OCH₃), HSi(CH₃)(OC(O)CH₃)₂,    HSi(CH₃)₂O—[Si(CH₃)₂O]₂.Si(CH₃)(OCH₃)₂, and HSi(CH₃)[O—N═C(CH₃)₂]₂    (wherein C₆H₅ represents a phenyl group).

The addition reaction of the crosslinkable-silyl-containing hydrosilanecompound to the vinyl polymer having a terminal alkenyl group isconducted in the presence of a hydrosilylation catalyst. Examples of thehydrosilylation catalyst include radical initiators, such as organicperoxides and azo compounds, and transition metal catalysts.

The radical initiator is not particularly limited but may be of anykind. Examples of the radical initiator include dialkyl peroxides suchas di-tert-butyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane,2,5-dimethyl-2,5-di(tert-butylperoxy)-3-hexyne, dicumylperoxide,tert-butylcumylperoxide, and α,α′-bis(tert-butylperoxy)isopropylbenzene;diacyl peroxides such as benzoyl peroxide, p-chlorobenzoyl peroxide,m-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and lauroylperoxide; peroxyesters such as tert-butyl peroxybenzoate;peroxydicarbonates such as diisopropyl peroxydicarbonate anddi-2-ethylhexyl peroxydicarbonate; and peroxyketals such as1,1-di(tert-butylperoxy)cyclohexane and1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane.

Examples of the transition metal catalyst include elemental platinum,alumina, silica, a substrate composed of, e.g., carbon black, containingdispersed solid platinum, chloroplatinic acid, complexes ofchloroplatinic acid with alcohol, aldehyde, ketone, and the like,platinum-olefin complexes, and a platinum(0)-divinyltetramethyldisiloxane complex. Examples of the catalyst otherthan the platinum compounds include RhCl(PPh₃)₃, RhCl₃, RuCl₃, IrCl₃,FeCl₃, AlCl₃, PdCl₂.H₂O, NiCl₂, and TiCl₄. These catalysts may be usedalone or in combination.

The hydrosilylation catalyst content is not particularly limited but ispreferably 10⁻¹ to 10⁻⁸ mol and more preferably 10⁻³ to 10⁻⁶ mol permole of terminal alkenyl groups of the vinyl polymer. A hydrosilylationcatalyst content less than 10⁻⁸ mol may result in insufficienthardening. The upper limit is preferably 10⁻¹ mol since thehydrosilylation catalyst is expensive.

When an alkenyl-terminated vinyl polymer is reacted with allyl alcoholor methallyl alcohol, a polymer terminus having an active group, such asa halogen group, and a hydroxyl group on neighboring carbon atoms isproduced as a result. This polymer terminus can be converted into anepoxy group by cyclization. The cyclization may be conducted by anymethod but preferably through reaction with an alkaline compound. Thealkaline compound is not particularly limited. Examples of the alkalinecompound include KOH, NaOH, Ca(OH)₂, ammonia, and various amines.

The hydroxyl group at the terminus of the vinyl polymer is convertedinto an alkenyl group by condensation with allyl chloride, allylbromide, or the like in the presence of the alkaline compound.Alternatively, the hydroxyl group is converted into an epoxy group bythe similar reaction in the presence of epichlorohydrin.

The hydroxyl or amino group at the terminus of the vinyl polymer may beconverted into a crosslinkable silyl group by the reaction with acompound having both a crosslinkable silyl group and a functional groupreactive with the hydroxyl or amino group. Examples of the functionalgroup reactive with the hydroxyl or amino group include halogen,carboxylic acid halide, carboxylic acid, and isocyanate. Isocyanate ispreferred since the compound is widely available, the requirements forthe reaction with the hydroxyl group are not so stringent, anddecomposition of the crosslinkable silyl groups is unlikely to occur.

The isocyanate compound having a crosslinkable silyl group is notparticularly limited and any known compound can be used. Specificexamples of the isocyanate compound are as follows:

-   (CH₃O)₃Si—(CH₂)_(n)—NCO,-   (CH₃O)₂(CH₃)Si—(CH₂)_(n)—NCO,-   (C₂H₅O)₃Si—(CH₂)_(n)—NCO,-   (C₂H₅O)₂(CH₃)Si—(CH₂)_(n)—NCO,-   (i-C₃H₇O)₃Si—(CH₂)_(n-)NCO,-   (i-C₃H₇O)₂(CH₃)Si(CH₂)_(n)—NCO,-   (CH₃O)₃Si—(CH₂)_(n)—NH—(CH₂)_(m)—NCO,-   (CH₃O)₂(CH₃)Si—(CH₂)_(n)—NH—(CH₂)_(m)—NCO,-   (C₂H₅O)₃Si—(CH₂)—NH—(CH₂)_(m)—NCO,-   (C₂H₅O)₂(CH₃)Si—(CH₂)_(n)—NH—(CH₂)_(m)—NCO,-   (i-C₃H₇O)₃Si—(CH₂)_(n)—NH—(CH₂)_(m)—NCO, and-   (i-C₃H₇O)₂(CH₃)Si—(CH₂)_(n)—NH—(CH₂)_(m)—NCO (wherein n and m each    represent an integer between 1 and 20).

For example, the reaction between a hydroxyl-terminated (meth)acrylicpolymer and a crosslinkable-silyl-containing isocyanate compound may beconducted in the presence or absence of a solvent. The reactiontemperature is preferably 0 to 100° C., and more preferably 20 to 50° C.In order to accelerate the reaction between the hydroxyl group and theisocyanate group, a tin catalyst or a tertiary amine catalyst may beused.

Specific examples of the tin catalyst include tin octylate, dibutyltindiacetate, dibutyltin dilaurate, dibutyltin mercaptide, dibutyltinthiocarboxylate, dibutyltin dimaleate, and dioctyltin thiocarboxylate.Examples of the tertiary amine catalyst include triethylamine,N,N-dimethylcyclohexylamine, N,N,N′,N′-tetramethylethylenediamine,N,N,N′,N′-tetramethylpropane-1,3-diamine,N,N,N′,N′-tetramethylhexane-1,6-diamine,N,N,N′,N″,N″-pentamethyldiethylenetriamine,N,N,N′,N″,N″-pentamethyldipropylenetriamine, tetramethylguanidine,triethylenediamine, N,N′-dimethylpiperazine, N-methylmorpholine,1,2-dimethylimidazole, dimethylaminoethanol, dimethylaminoethoxyethanol,N,N,N′-trimethylaminoethylethanolamine,N-methyl-N′-(2-hydroxyethyl)piperazine, N-(2-hydroxyethyl)morpholine,bis(2-dimethylaminoethyl)ether, and ethylene glycolbis(3-dimethyl)aminopropyl ether.

The vinyl polymer having a terminal functional group produced accordingto the present invention may be used in a curable composition. Thecurable composition of the present invention may contain the vinylpolymer having a terminal functional group, a plasticizer, a filler, andthe like. Examples of the plasticizer include phthalic acid esters suchas dioctyl phthalate, dibutyl phthalate, diheptyl phthalate,di(2-ethylhexyl)phthalate, and butylbenzyl phthalate; nonaromaticdibasic acid esters such as dioctyl adipate, dioctyl sebacate, dibutylsebacate, and isodecyl succinate; aliphatic esters such as butyl oleateand methyl acetyl ricinolate; esters of polyalkylene glycol, such asdiethylene glycol dibenzoate, triethylene glycol dibenzoate, andpentaerythritol ester; phosphoric esters such as tricresyl phosphate andtributyl phosphate; trimellitic esters; polystyrenes such as polystyreneand poly-α-methylstyrene; polybutadiene, polybutene, polyisobutylene,butadiene-acrylonitrile, and polychloroprene; chlorinated paraffins;hydrocarbon oils such as alkyldiphenyl and partially hydrogenatedterphenyl; process oils; polyethers such as polyether polyols, e.g.,polyethylene glycol, polypropylene glycol, and polytetramethyleneglycol, and derivatives obtained by converting the hydroxyl groups ofthese polyether polyols into ester or ether groups; epoxy plasticizerssuch as epoxidized soybean oil and benzyl epoxy stearate; polyesterplasticizers obtained from dibasic acids, such as sebacic acid, adipicacid, azelaic acid, and phthalic acid, and dihydric alcohols, such asethylene glycol, diethylene glycol, triethylene glycol, propyleneglycol, and dipropylene glycol; and vinyl polymers, such as acrylicplasticizers, prepared by polymerizing vinyl monomers by variousmethods. Examples of the filler include reinforcing fillers such as woodflour, pulp, cotton chip, asbestos, glass fiber, carbon fiber, mica,walnut shell flour, rice hull flour, graphite, diatomite, white clay,silica (fumed silica, precipitated silica, crystalline silica, fusedsilica, dolomite, silicic acid anhydride, and hydrated silica), andcarbon black; fillers such as calcium carbonate (e.g. heavy calciumcarbonate and colloidal calcium carbonate), magnesium carbonate,diatomite, calcined clay, clay, talc, titanium oxide, bentonite, organicbentonite, ferric oxide, ferric oxide red, aluminum fine powder, flintpowder, zinc oxide, active zinc oxide, zinc dust, zinc carbonate, andshirasu balloon; and fibrous fillers such as asbestos, glass fiber andfilament, carbon fiber, Kevlar fiber, and polyethylene fiber. Thecurable composition of the present invention may contain a curing agentor curing catalyst, if necessary.

By using an alkenyl-terminated vinyl polymer, a curable compositioncontaining an alkenyl-terminated vinyl polymer (A) and ahydrosilyl-containing compound (curing agent) (B) can be produced.

The alkenyl-terminated vinyl polymer (A) may be of a single componenttype or a multiple component type.

The hydrosilyl-containing compound (B) is not particularly limited, andvarious compounds may be used. Examples of the hydrosilyl-containingcompound (B) include linear polysiloxanes represented by generalformulae (14) and (15):R²⁴ ₃SiO—[Si(R²⁴)₂O]_(a)—[Si(H)(R²⁵)O]_(b)—[Si(R²⁵)(R²⁶)O]—SiR²⁴ ₃  (14)HR²⁴ ₂SiO—[Si(R²⁴)₂O]_(a)—[Si(H)(R²⁵)O]_(b)—[Si(R²⁵)(R²⁶)O]_(c)—SiR²⁴₂H  (15)(wherein R²⁴ and R²⁵ each represent a C₁-C₆ alkyl group or a phenylgroup; R²⁶ represents a C₁-C₁₀ alkyl group or a C₇-C₁₀ aralkyl group; ais an integer satisfying 0≦a≦100; b is an integer satisfying 2≦b≦100;and c is an integer satisfying 0≦c≦100), and cyclic siloxanesrepresented by general formula (16):

(wherein R²⁴ and R²⁵ each represent a C₁-C₆ alkyl group or a phenylgroup; R²⁶ represents a C₁-C₁₀ alkyl group or a C₇-C₁₀ aralkyl group; dis an integer satisfying 0≦d≦8; e is an integer satisfying 2≦e≦10; f isan integer satisfying 0≦f≦8; and 3≦d+e+f≦10).

These hydrosilyl-containing compounds (B) may be used alone or incombination. Among these siloxanes, phenyl-containing linear siloxanesrepresented by general formula (17):(CH₃)₃SiO—[Si(H)(CH₃)O]_(g)—[Si(C₆H₅)₂O]_(h)—Si(CH₃)₃  (17)and general formula (18):(CH₃)₃SiO—[Si(H)(CH₃)O]_(g)—[Si(CH₃){CH₂C(H)(R²⁷)C₆H₅}O]_(h)—Si(CH₃)₃  (18)(wherein R²⁷ represents hydrogen or a methyl group; g is an integersatisfying 2≦g≦100; h is an integer satisfying 0≦h≦100; and C₆H₅represents a phenyl group), and cyclic siloxanes represented by generalformula (19):

and general formula (20)

(wherein R²⁷ represents hydrogen or a methyl group; i is an integersatisfying 2≦i≦10; j is an integer satisfying 0≦j≦8; 3≦i+j≦10; and C₆H₅represents a phenyl group).

The hydrosilyl-containing compound (B) may contain at least twohydrosilyl groups. The curing agent containing two or more hydrosilylgroups may be a compound prepared by addition reaction between ahydrosilyl-containing compound represented by one of general formulae(14) to (20) and a low-molecular-weight compound having two or morealkenyl groups per molecule, such that the hydrosilyl groups partiallyremain after the termination of the addition reaction. Various compoundsmay be used as the compound having two alkenyl groups per molecule.Examples of such compounds include hydrocarbons such as 1,4-pentadiene,1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, and1,9-decadiene; ethers such as O,O′-diallyl bisphenol A and 3,3′-diallylbisphenol A; esters such as diallyl phthalate, diallyl isophthalate,triallyl trimellitate, and tetraallyl pyromellitate; and carbonates suchas diethylene glycol diallyl carbonate. The curable composition of thepresent invention may be prepared by gradually supplying dropwise thealkenyl-terminated vinyl polymer (A) to an excessive amount of thehydrosilyl-containing compound represented by one of general formulae(14) to (20) in the presence of a hydrosilylation catalyst. Amongcompounds having two or more hydrosilyl groups, those described beloware preferred in view of the availability of the starting materials,ease of removing the excess siloxane, and compatibility with thealkenyl-containing vinyl polymer (A):

(wherein n is an integer between 2 and 4; and m is an integer between 5and 10).

The alkenyl-terminated vinyl polymer (A) and the hydrosilyl-containingcompound (B) may be mixed at any ratio. Preferably, the molar ratio ofthe alkenyl groups to the hydrosilyl groups is in the range of 5 to 0.2,and more preferably in the range of 2.5 to 0.4 in view of curability. Amolar ratio exceeding 5 results in insufficient cure, and the resultingcured product is sticky and has low strength. At a molar ratio less than0.2, large quantities of active hydrosilyl groups remain in the productafter curing, resulting in generation of cracks and voids. Thus, ahomogeneous cured product having a sufficient strength cannot beobtained.

The curing reaction between the alkenyl-terminated vinyl polymer (A) andthe hydrosilyl-containing compound (B) proceeds by heating the mixtureof these two components. In order to accelerate the reaction, ahydrosilylation catalyst is used. Examples of the hydrosilylationcatalyst are described above.

A crosslinkable-silyl-terminated vinyl polymer (C) may be used toproduce a curable composition containing this polymer as the maincomponent.

The crosslinkable-silyl-terminated vinyl polymer (C) cures into athree-dimensional structure through crosslinking reaction when thecrosslinkable-silyl-terminated vinyl polymer (C) is put into contactwith moisture. The rate of hydrolysis depends on the temperature,humidity, and the type of the hydrolyzable group. An appropriatehydrolyzable group must be selected according to the requiredconditions.

In order to accelerate the curing reaction, a curing catalyst (D) may besupplied. Examples of condensation catalysts include titanates such astetrabutyl titanate and tetrapropyl titanate; organotin compounds suchas dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, tinoctylate, and tin naphthenate; amine compounds, such as lead octylate,butylamine, octylamine, dibutylamine, monoethanolamine, diethanolamine,triethanolamine, diethylenetriamine, triethylenetetramine, oleylamine,octylamine, cyclohexylamine, benzylamine, diethylaminopropylamine,xylylenediamine, triethylenediamine, guanidine, diphenylguanidine,2,4,6-tris(dimethylaminomethyl)phenol, morpholine, N-methylmorpholine,and 1,3-diazabicyclo(5,4,6)undecene-7, and carboxylates thereof;low-molecular-weight polyamide resins obtained from excessive polyamineand polybasic acid; reaction products of excessive polyamine and epoxycompounds; amino-containing silane coupling agents, e.g., known silanolcatalysts such as γ-aminopropyltrimethoxysilane andN-(β-aminoethyl)aminopropylmethyldimethoxysilane. These catalysts may beused alone or in combination. The amount of the catalyst used ispreferably 0 to 10 percent by weight of thecrosslinkable-silyl-terminated vinyl polymer (C). When the hydrolyzablegroup Y is an alkoxy group, it is preferable to use a curing catalystsince the curing rate is low with this polymer alone.

When the crosslinkable-silyl-terminated vinyl polymer (C), i.e., themain component, is cured in the presence of the condensation catalyst(D) as required, a homogeneous cured product can be obtained as aresult. The curing conditions are not particularly limited but curing isgenerally conducted at a temperature of 0 to 100° C., and preferably 10to 50° C., for about one hour to about one week. The characteristics ofthe cured product depend on the main chain skeleton and the molecularweight of the polymer; and various forms of products, i.e., from rubberyto resinous products, can be obtained.

A curable composition containing a hydroxyl-terminated vinyl polymer (E)as the main component and a compound (F) having at least two functionalgroups reactive to a hydroxyl group can be produced.

The compound (F) having at least two functional groups reactive to ahydroxyl group is not particularly limited. Examples thereof includepolyisocyanate compounds having at least two isocyanate groups permolecule, methylolated melamine and alkyl ethers thereof; aminoplastresins such as low condensates; and polyfunctional carboxylic acids andhalides thereof.

As the polyisocyanate compound having at least two isocyanate groups permolecule, those known in the art may be used. Examples of thepolyisocyanate compound include isocyanate compounds such as2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate,4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylenediisocyanate, metaxylylene diisocyanate, 1,5-naphthalene diisocyanate,hydrogenated diphenylmethane diisocyanate, hydrogenated tolylenediisocyanate, hydrogenated xylylene diisocyanate, isophoronediisocyanate, and triisocyanate, e.g., B-45 produced by Ipposha OilIndustries Co., Ltd.; biuret polyisocyanate compounds, such as Sumidur N(produced by Sumitomo-Bayer Urethane Co., Ltd.); polyisocyanatecompounds having an isocyanurate ring, such as Desmodurs IL and HL(produced by Bayer A. G.) and Colonate EH (produced by NipponPolyurethane Kogyo Co., Ltd.); adduct polyisocyanate compounds such asSumidur L (produced by Sumitomo-Bayer Urethane Co., Ltd.); and adductpolyisocyanate compounds such as Colonate HL (produced by NipponPolyurethane Kogyo Co., Ltd.). Blocked isocyanates may be used. Thesecompounds may be used alone or in combination.

The mixing ratio of the hydroxyl-terminated vinyl polymer (E) to thecompound (F) having at least two isocyanate groups is not particularlylimited. For example, the ratio of the isocyanate groups to the hydroxylgroups (NCO/OH, molar ratio) is preferably 0.5 to 3.0, and morepreferably 0.8 to 2.0.

If necessary, a known catalyst, such as the organotin compound or thetertiary amine described above, may be supplied to promote the curingreaction between the hydroxyl-terminated vinyl polymer (E) and thecompound having at least two isocyanate groups.

The aminoplast resin is not particularly limited. Examples of theaminoplast resin include adducts (methylol compounds) of melamine andformaldehyde, low condensates of melamine and formaldehyde, alkyl ethersthereof, and urea resins. These may be used alone or in combination. Aknown catalyst, such as paratoluenesulfonic acid or benzenesulfonicacid, may be supplied to promote the curing reaction between thehydroxyl-terminated (meth)acrylic polymer and the aminoplast resin.

The polyfunctional carboxylic acid is not particularly limited. Examplesof the polyfunctional carboxylic acid include oxalic acid, malonic acid,succinic acid, glutaric acid, adipic acid, phthalic acid, phthalicanhydride, terephthalic acid, trimellitic acid, pyromellitic acid,maleic acid, maleic anhydride, fumaric acid, and itaconic acid; andanhydrides and halides of these polyfunctional carboxylic acids. Thesecompounds may be used alone or in combination.

A homogeneous cured product with a satisfactorily cured interior can beobtained by reacting the hydroxyl-terminated vinyl polymer (E) with thecompound (F) having at least two functional groups reactive to thehydroxyl group in the presence of, if necessary, a curing catalyst. Thecuring conditions are not particularly limited; however, curing isgenerally performed at 0 to 100° C., and more preferably at 20 to 80° C.

The characteristics of the cured product depend on the main chainskeletons and the molecular weights of the hydroxyl-terminated vinylpolymer (E) and the compound (F) having at least two functional groupsreactive to the hydroxyl group. Various forms of products, i.e., fromrubbery to resinous products, can be obtained.

When an epoxy-terminated vinyl polymer is used, a curable compositioncontaining an epoxy-terminated vinyl polymer (G) and a compound(hardener) (H) having at least two carboxyl groups per molecule can beprepared.

As the compound (H) having at least two carboxyl groups per molecule,various compounds may be used. Examples of such compounds includealiphatic amines, aromatic amines, acid anhydrides, urea, melamine, andphenol resins.

The cured product made from the epoxy-terminated vinyl polymer (G) andthe compound (F) having at least two carboxyl groups per molecule can beused in, for example, sealing materials, adhesives, pressure-sensitiveadhesives, elastic adhesives, paints, powder coatings, foamed products,potting agents for electric and electronic parts, films, moldingmaterials, and artificial marble.

As is described above, a functional-group-terminated vinyl polymer canbe produced in the present invention. During the production, thepolymerization solvent and the vinyl monomer are recovered after thepolymerization while the ability for atomic transfer radicalpolymerization is maintained, and are reused in high yields. Afterremoving the polymerization solvent and the vinyl monomer for recovery,a functional-group-introducing agent is supplied to the system tointroduce functional groups into the polymer. Thisfunctional-group-introducing agent can be recovered after the completionof the functional group introduction and reused in high yields. Asolvent may be used during the functional group introduction. In otherwords, according to the present invention, controlled introduction offunctional groups to the polymer termini is possible, and the excessfunctional-group-introducing agent can be reused. Thus,functional-group-terminated polymers can be advantageously produced.Moreover, the resulting functional-group-terminated polymer can besubjected to an appropriate functional group conversion, such ashydrosilylation or epoxidation, or can be mixed with an appropriatecrosslinking agent to prepare a curable composition.

The present invention will now be specifically described by way ofnonlimiting examples. In the examples and comparative examples below,the term “parts” means “parts by weight” and “percent (%)” means“percent (%) by weight”.

In the examples, the number-average molecular weight and the molecularweight distribution (the ratio of the weight-average molecular weight tothe number-average molecular weight) were determined by gel permeationchromatography (GPC) calibrated with polystyrene standard samples.

Shodex GPC K-804 (produced by Showa Denko K. K.) packed with crosslinkedpolystyrene gel was used as the GPC column, and chloroform was used asthe GPC solvent (mobile phase). The number of functional groupsintroduced per polymer molecule was calculated based on theconcentration analyzed by ¹H-NMR analysis and on the number-averagemolecular weight determined by GPC.

EXAMPLE 1

In a 250 L pressure reactor, 1.01 kg (7.02 mol) of copper(I) bromide and10.6 kg of acetonitrile were charged, and were stirred under a nitrogengas stream at 65° C. for 16 minutes under heating. To the resultingmixture, 2.11 kg (5.85 mol) of diethyl 2,5-dibromoadipate and 24.0 kg(187 mol) of butyl acrylate were supplied, and the mixture was stirredfor 40 minutes at 65° C. under heating. Subsequently, 20.3 g (0.117 mol)of pentamethyldiethylenetriamine was supplied to initiate reaction, andthe stirring was continued at 80° C. under heating. To the mixture,101.5 g (0.585 mol) of pentamethyldiethylenetriamine was supplied. Fortysix minutes after the initiation of the reaction, 96.0 kg (749 mol) ofbutyl acrylate was intermittently supplied dropwise over 180 minutes.During this time period, 81.2 g (0.468 mol) ofpentamethyldiethylenetriamine was supplied to the mixture. The butylacrylate conversion rate reached 95.9% 346 minutes after the initiationof the reaction. The pressure in the reactor was reduced to removevolatile components. To the mixture, 31.7 kg of acetonitrile (dielectricconstant: 38), 12.9 kg (117 mol) of 1,7-octadiene (dielectric constant:1 to 3), and 406 g (2.34 mol) of pentamethyldiethylenetriamine weresupplied 434 minutes after the initiation of the reaction. The stirringwas continued at 80° C. under heating. The heating was stopped 809minutes after the initiation of the reaction. A solution containing apolymer [1] was obtained as a result. The polymer [1] had anumber-average molecular weight of 26,400 and a molecular weightdistribution of 1.23. According to ¹H-NMR analysis, the number ofalkenyl groups per polymer molecule was 1.9, and the number of polymertermini having no alkenyl groups was zero.

EXAMPLE 2

A mixture containing the polymer [1] was concentrated. The residuemixture was diluted with methylcyclohexane and solid components wereremoved. To the resulting methylcyclohexane solution of the polymer, 4parts of adsorbents (2 parts of Kyowaad 500SH and 2 parts of Kyowaad700SL, produced by Kyowa Chemical Industry Co., Ltd.) to 100 parts ofthe polymer were supplied. The resulting mixture was stirred underheating in a mixed-gas atmosphere of oxygen and nitrogen. Solidcomponents were removed, and the polymer solution was concentrated toobtain a polymer [1′]. The molecular weight distribution of the polymer[1′] was 1.30.

COMPARATIVE EXAMPLE 1

In a 500 mL flask, 2.52 g (17.6 mmol) of copper(I) bromide and 33.6 mL(26.4 g) of acetonitrile were charged and stirred under a nitrogen gasstream at 70° C. for 30 minutes under heating. To the resulting mixture,5.27 g (14.6 mmol) of diethyl 2,5-dibromoadipate and 336 mL (300 g, 2.34mol) of butyl acrylate were supplied, and the resulting mixture wasstirred at 70° C. for 20 minutes under heating. To the resultingmixture, 0.122 mL (0.101 g, 0.585 mmol) of pentamethyldiethylenetriaminewas supplied to initiate reaction. The stirring was continued at 80° C.under heating, and 0.366 mL (0.303 g, 1.76 mmol) ofpentamethyldiethylenetriamine was supplied. The butyl acrylateconversion rate reached 98.6% 200 minutes after the initiation of thereaction. To the resulting mixture, 43.2 mL (32.2 g, 0.293 mol) of1,7-octadiene and 1.22 mL (1.01 g, 5.85 mmol) ofpentamethyldiethylenetriamine were supplied, and the resulting mixturewas stirred at 80° C. under heating. The heating was stopped 440 minutesafter the initiation of the reaction, and a solution containing apolymer [4] was obtained as a result. The polymer [4] had anumber-average molecular weight of 26,800 and a molecular weightdistribution of 1.32. The number of alkenyl groups per polymer moleculedetermined by ¹H-NMR analysis was 2.9. The number of polymer terminihaving no alkenyl groups was 0.3.

COMPARATIVE EXAMPLE 2

A mixture containing the polymer [4] was processed as in EXAMPLE 2 toobtain a polymer [4′]. The molecular weight distribution of the polymer[4′] was 1.51.

EXAMPLE 3

In a 2 L flask, 8.39 g (58.5 mmol) of copper(I) bromide and 112 mL (87.9g) of acetonitrile were charged and stirred under a nitrogen gas streamat 70° C. for 20 minutes under heating. To the resulting mixture, 17.6 g(48.8 mmol) of diethyl 2,5-dibromoadipate and 224 mL (200 g, 1.56 mol)of butyl acrylate were supplied, and the resulting mixture was stirredat 80° C. for 40 minutes under heating. To the resulting mixture, 0.41mL (0.338 g, 1.95 mmol) of pentamethyldiethylenetriamine was supplied toinitiate reaction. To the resulting mixture, 1.23 mL (1.01 g, 5.85 mmol)of pentamethyldiethylenetriamine was supplied, and the stirring wascontinued at 80° C. under heating. Thirty-five minutes after theinitiation of the reaction, 895 mL (800 g, 6.24 mol) of butyl acrylatewas intermittently supplied dropwise over 145 minutes. During this timeperiod, 0.41 mL (0.338 g, 1.95 mmol) of pentamethyldiethylenetriaminewas supplied. The butyl acrylate conversion rate reached 95.9% 240minutes after the initiation of the reaction. The pressure in thereactor is reduced to remove volatile components. To the resultingmixture, 336 mL (264 g) of acetonitrile, 144 mL (107 g, 0.975 mol) of1,7-octadiene, and 4.1 mL (3.38 g, 19.5 mmol) ofpentamethyldiethylenetriamine were supplied 360 minutes after theinitiation of the reaction. The stirring was continued at 80° C. underheating. The heating was stopped 740 minutes after the initiation of thereaction. A solution containing a polymer [2] was obtained as a result.The polymer [2] had a number-average molecular weight of 24,000 and amolecular weight distribution of 1.17. The number of alkenyl groups perpolymer molecule determined by ¹H-NMR analysis was 1.7. The number ofpolymer termini having no alkenyl groups was zero.

EXAMPLE 4

A mixture containing the polymer [2] was concentrated. The residuemixture was diluted with toluene to remove solid components. To theresulting toluene solution of the polymer, 4 parts of adsorbents (2parts of Kyowaad 500SH and 2 parts of Kyowaad 700SL, produced by KyowaChemical Industry Co., Ltd.) to 100 parts of the polymer were supplied.The resulting mixture was stirred under heating under a mixed-gasatmosphere of oxygen and nitrogen. After removal of solid components,the polymer solution was concentrated. The residue solution was dilutedwith N,N-dimethylacetoamide, and the resulting solution was stirred for8 hours at 100° C. under heating in the presence of potassium acetate.The polymer solution was concentrated and diluted with toluene to removesolid components. To the resulting xylene solution of the polymer, 50parts of an adsorbent (50 parts of Kyowaad 700PEL, produced by KyowaChemical Industry Co., Ltd.) to 100 parts of the polymer was supplied,and the resulting mixture was stirred under heating under a mixed-gasatmosphere of oxygen and nitrogen. After removal of solid components,the solution was concentrated to obtain a polymer. The polymer was thenmixed with dimethoxymethylsilane (3 molar equivalents of alkenylgroups), methyl ortho-formate (1 molar equivalent of alkenyl groups),and a platinum catalyst (30 mg of platinum per 1 kg of the polymer),i.e., a xylene solution of abis(1,3-divinyl-1,1,3,3-tetramethyldisiloxane) platinum complex,hereinafter simply referred to as “platinum catalyst”. The resultingmixture was stirred under a nitrogen atmosphere at 80° C. for 1 hourunder heating. The disappearance of the alkenyl groups by the reactionwas confirmed by ¹H-NMR analysis. The reaction mixture was thenconcentrated to obtain a target methoxysilyl-containing polymer [2′].The polymer [2′] had a number-average molecular weight of 25,600 and amolecular weight distribution of 1.26. The number of silyl groupsintroduced per polymer molecule was 1.8.

EXAMPLE 5

A mixture of 100 parts of the methoxysilyl-containing polymer [2′]obtained in EXAMPLE 4, 150 parts of calcium carbonate (Hakuenka CCR,produced by Shiraishi Kogyo Kaisha, Ltd.), and 50 parts of DOP (dioctylphthalate, produced by Kyowa Hakko Kogyo Co., Ltd.) was thoroughly mixedwith three paint rollers. The resulting mixture was aged in the presenceof a tetravalent Sn catalyst (dibutyltin diacetylacetonate) for two daysindoor and three days at 50° C. to obtain a cured sheet. The tensilecharacteristics of the cured sheet were evaluated (Autograph availablefrom Shimadzu Corporation, measuring temperature: 23° C., stress rate:200 mm/sec, No. 2(1/3) dumbbell specimen). The strength at break was0.77 MPa and the elongation at break was 430%.

COMPARATIVE EXAMPLE 3

In a 20 L reactor equipped with a reflux tube and a stirrer, 83.9 g(0.585 mol) of copper(I) bromide was charged, and the reactor was purgedwith nitrogen gas. Into the reactor, 879 g of acetonitrile was supplied,and the resulting mixture was stirred in an oil bath at 70° C. for 45minutes. To the resulting mixture, 2.00 kg (25.6 mol) of butyl acrylate,diethyl 2,5-dibromoadipate (176 g, 0.488 mol), and 4.07 mL (3.38 g, 19.5mmol) of pentamethyldiethylenetriamine were supplied to initiatereaction. To the resulting mixture, 8.14 mL (6.76 g, 39.0 mmol) ofpentamethyldiethylenetriamine was supplied, followed by stirring underheating at 70° C. Sixty minutes after the initiation of the reaction,8.00 kg (102 mol) of the butyl acrylate was continuously supplieddropwise over 170 minutes, during which 8.14 mL (6.76 g, 39.0 mmol) ofpentamethyldiethylenetriamine was also supplied. The butyl acrylateconversion rate reached 96.7% 450 minutes after the initiation of thereaction. To the resulting mixture, 2.88 L (2.15 kg, 19.5 mol) of1,7-octadiene and 30.5 mL (25.4 g, 146 mmol) ofpentamethyldiethylenetriamine were supplied, followed by stirring at 70°C. for 240 minutes under heating.

The reaction mixture was diluted with toluene to remove solidcomponents. The resulting mixture was passed through an active aluminacolumn, and the volatile components of the mixture were removed byreduced-pressure distillation. An alkenyl-terminated polymer [5] wasobtained as a result. The polymer [5] had a number-average molecularweight of 25,100 and a molecular weight distribution of 1.34. Theaverage number of alkenyl groups per polymer molecule determined by¹H-NMR analysis was 3.1.

COMPARATIVE EXAMPLE 4

The polymer [5] was diluted with N,N-dimethylacetoamide and theresulting solution was stirred under heating at 100° C. for 8 hours inthe presence of potassium acetate. After heating under a reducedpressure, the solution was diluted with toluene and solid componentswere removed. To the resulting toluene solution of the polymer, 15 partsof adsorbents (10 parts of Kyowaad 500SH/5 parts of Kyowaad 700SL,produced by Kyowa Chemical Industry Co., Ltd.) to 100 parts of thepolymer were supplied, and the resulting mixture was stirred underheating at 130° C. After the solid components were removed, the polymersolution was concentrated to obtain a polymer. The polymer was mixedwith dimethoxymethylsilane (3 molar equivalents of alkenyl groups),methyl ortho-formate (1 molar equivalent of alkenyl groups), and aplatinum catalyst (60 mg of platinum per 1 kg of the polymer). Theresulting mixture was stirred for 5 hours under heating at 100° C. Afterthe disappearance of alkenyl groups due to the reaction was confirmed by¹H-NMR analysis, the reaction mixture was concentrated to obtain atarget methoxysilyl-containing polymer [5′]. The methoxysilyl-containingpolymer [5′] had a number-average molecular weight of 28,900 and amolecular weight distribution of 1.90. The number of silyl groupsintroduced per polymer molecule was 1.9.

COMPARATIVE EXAMPLE 5

A mixture of 100 parts of the methoxysilyl-containing polymer [5′]obtained in COMPARATIVE EXAMPLE 4, 150 parts of calcium carbonate(Hakuenka CCR, produced by Shiraishi Kogyo Kaisha, Ltd.), and 50 partsof DOP (dioctyl phthalate, produced by Kyowa Hakko Kogyo Co., Ltd.) wasthoroughly mixed with three paint rollers. The resulting mixture wasaged in the presence of a tetravalent Sn catalyst (dibutyltindiacetylacetonate) for two days indoor and three days at 50° C. toobtain a cured sheet. The tensile characteristics of the cured sheetwere evaluated (Autograph available from Shimadzu Corporation, measuringtemperature: 23° C., stress rate: 200 mm/sec, No. 2(1/3) dumbbellspecimen). The strength at break was 0.95 MPa and the elongation atbreak was 320%.

EXAMPLE 6

In a 250 L pressure reactor, 1.11 kg (7.72 mol) of copper(I) bromide and9.95 kg of acetonitrile were charged and stirred under a nitrogen gasstream at 65° C. for 15 minutes under heating. To the resulting mixture,3.09 kg (8.58 mol) of diethyl 2,5-dibromoadipate, 6.60 kg (51.5 mol) ofbutyl acrylate, 9.49 kg (94.7 mol) of ethyl acrylate, and 7.77 kg (59.7mol) of 2-methoxyethyl acrylate were supplied. The resulting mixture wasstirred at 65° C. for 43 minutes under heating, and 22.3 g (0.129 mol)of pentamethyldiethylenetriamine was supplied to initiate reaction. Thestirring was continued at 80° C. under heating, and 112 g (0.644 mol) ofpentamethyldiethylenetriamine was supplied. Fifty seven minutes afterthe initiation of the reaction, 26.4 kg (206 mol) of butyl acrylate,37.9 kg (379 mol) of ethyl acrylate, and 31.3 kg (239 mol) of2-methoxyethyl acrylate were intermittently supplied dropwise over 180minutes. During this time period, 89.2 g (0.515 mol) ofpentamethyldiethylenetriamine was also supplied. The pressure in thereactor was reduced 602 minutes after the initiation of the reaction toremove volatile components. The average of the conversion rates of theethyl acrylate, butyl acrylate, and 2-methoxyethyl acrylate reached95.3% 720 minutes after the initiation of the reaction. To the resultingmixture, 9.95 kg of acetonitrile, 28.4 kg (257 mol) of 1,7-octadiene,446 g (2.57 mol) of pentamethyldiethylenetriamine were supplied, and thestirring was continued at 80° C. under heating. The heating was stopped1,340 minutes after the initiation of the reaction. A solutioncontaining a polymer [3] was obtained as a result. The polymer [3] had anumber-average molecular weight of 17,100 and a molecular weightdistribution of 1.16. The number of alkenyl groups per polymer moleculedetermined by ¹H-NMR analysis was 1.6. The number of polymer terminihaving no alkenyl groups was zero.

EXAMPLE 7

The solution of a mixture containing the polymer [3] was concentratedand then diluted with toluene to remove solid components. The resultingtoluene solution of the polymer was mixed with 4 parts of adsorbents (2parts of Kyowaad 500SH and 2 parts of Kyowaad 700SL, produced by KyowaChemical Industry Co., Ltd.) to 100 parts of the polymer, and theresulting mixture was stirred under heating under a mixed-gas atmosphereof oxygen and nitrogen. After the solid components were removed, thepolymer solution was concentrated. The residue solution was diluted withN,N-dimethylacetoamide, and the resulting solution was stirred for 8hours at 100° C. under heating in the presence of potassium acetate. Thepolymer solution was then concentrated. The toluene solution of thepolymer was then mixed with 10 parts of adsorbents (5 parts of Kyowaad500SH/5 parts of Kyowaad 700SL, produced by Kyowa Chemical Industry Co.,Ltd.) to 100 parts of the polymer. The resulting mixture was stirredunder heating under a mixed-gas atmosphere of oxygen and nitrogen. Afterremoval of solid components, the polymer solution was concentrated toobtain a polymer [3′].

EXAMPLE 8

A mixture of 100 parts of the polymer [3′] and 1.8 molar equivalent of alinear siloxane (containing, on average, five hydrosilyl groups and fivesubstituents [—CH₂—CH(CH₃)—C₆H₅] per molecule; the Si—H group contentbeing 3.70 mmol/g) relative to alkenyl group was prepared. A platinumcatalyst (10 to 100 mg relative to 1 kg of polymer based on platinum)was supplied to the mixture. The resulting mixture was homogeneouslymixed and was rapidly cured by heating at 130° C. A rubbery product wasobtained as a result. The tensile characteristics of the product wereevaluated using Autograph available from Shimadzu Corporation (measuringtemperature: 23° C., stress rate: 200 mm/sec, No. 2(1/3) dumbbellspecimen). The strength at break was 0.55 MPa and the elongation atbreak was 230%.

COMPARATIVE EXAMPLE 6

In a 50 L reactor, 270 g (1.88 mol) of copper(I) bromide and 2.43 kg ofacetonitrile were charged and stirred at 65° C. for 19 minutes underheating under a nitrogen gas stream. To the resulting mixture, 753 g(2.09 mol) of diethyl 2,5-dibromoadipate, 1.61 kg (12.6 mol) of butylacrylate, 2.31 kg (23.1 mol) of ethyl acrylate, and 1.90 kg (14.6 mol)of 2-methoxyethyl acrylate were supplied, and the resulting mixture wasstirred at 80° C. for 30 minutes under heating. To the resultingmixture, 13.1 mL (10.8 g, 62.8 mmol) of pentamethyldiethylenetriaminewas supplied to initiate reaction. Another 26.2 mL (21.6 g, 126 mmol) ofpentamethyldiethylenetriamine was supplied, and the stirring wascontinued at 80° C. under heating. Sixty five minutes after theinitiation of the reaction, 6.44 kg (50.4 mol) of butyl acrylate, 9.24kg (92.4 mol) of ethyl acrylate, and 7.60 kg (58.4 mol) of2-methoxyethyl acrylate were intermittently supplied dropwise over 103minutes. During this time period, 26.2 mL (21.6 g, 126 mmol) ofpentamethyldiethylenetriamine was further supplied. The average of theconversion rates of the ethyl acrylate, butyl acrylate, and2-methoxyethyl acrylate reached 96.8% 305 minutes after the initiationof the reaction. To this mixture, 6.92 kg (62.8 mol) of 1,7-octadieneand 131 mL (109 g, 0.628 mol) of pentamethyldiethylenetriamine weresupplied, and the stirring was continued at 80° C. under heating. Theheating was stopped 605 minutes after the initiation of the reaction. Asolution containing a polymer [6] was obtained as a result. The polymer[6] had a number-average molecular weight of 17,000 and a molecularweight distribution of 1.13. The number of alkenyl groups per polymermolecule determined by ¹H-NMR analysis was 2.5.

COMPARATIVE EXAMPLE 7

A mixture containing the polymer [6] was heated under a reduced pressureand diluted with toluene to remove solid components. The resultingsolution was diluted with N,N-dimethylacetoamide. The diluted solutionwas stirred for 8 hours at 100° C. under heating in the presence ofpotassium acetate. The resulting solution was heated under a reducedpressure and diluted with toluene to remove solid components. Thetoluene solution of the polymer was mixed with 15 parts of adsorbents(10 parts of Kyowaad 500SH/5 parts of Kyowaad 700SL, produced by KyowaChemical Industry Co., Ltd.) to 100 parts of the polymer. The resultingmixture was stirred at 130° C. under heating. Solid components were thenremoved, and the polymer solution was concentrated. A polymer [6′] wasobtained as a result.

COMPARATIVE EXAMPLE 8

A mixture of 100 parts of the polymer [6′] and 1.8 molar equivalent of alinear siloxane (containing, on average, five hydrosilyl groups and fivesubstituents [—CH₂—CH(CH₃)—C₆H₅] per molecule; the Si—H group contentbeing 3.70 mmol/g) relative to alkenyl groups was prepared. A platinumcatalyst (10 to 100 mg relative to 1 kg of polymer based on platinum)was supplied to the mixture. The resulting mixture was homogeneouslymixed and was rapidly cured by heating at 130° C. A rubbery product wasobtained as a result. The tensile characteristics of the product wereevaluated (Autograph available from Shimadzu Corporation, measuringtemperature: 23° C., stress rate: 200 mm/sec, No. 2(1/3) dumbbellspecimen). The strength at break was 0.61 MPa and the elongation atbreak was 160%.

The results are shown in Tables below. TABLE 1 Number- Molecular averageweight molecular distribution Fn Example Polymer weight (Mn) (Mw/Mn) Fn(alkenyl) (Br) 1 1 26,400 1.23 1.9 0.0 2 1′ — 1.30 — — Comparative 426,800 1.32 2.9 0.3 Example 1 Comparative 4′ — 1.51 — — Example 2*Fn (alkenyl): the number of alkenyl groups per polymer molecule.Fn (Br): the number of termini having no functional groups introducedper polymer molecule.“—”: Not determined

TABLE 2 Number-average Molecular weight molecular weight distributionExample Polymer (Mn) (Mw/Mn) Fn (alkenyl) Fn (Br) Fn (Si) Tb (MPa) Eb(%) 3 2 24,000 1.27 1.7 0 — — — 4 2′ 25,600 1.26 — 0 1.8 — — 5 2′ — — —— — 0.77 430 Comparative 5 25,100 1.34 3.1 — — — — Example 3 Comparative5′ 28,900 1.90 — — 1.9 — — Example 4 Comparative 5′ — — — — — 0.95 320Example 5*Fn (alkenyl): the number of alkenyl groups per polymer molecule.Fn (Br): the number of termini having no functional groups introducedper polymer molecule.Fn (Si): the number of silyl groups per polymer molecule.Tb: tensile strength at breakEb: elongation at break.“—”: Not determined.

TABLE 3 Number-average Molecular weight molecular weight distributionExample Polymer (Mn) (Mw/Mn) Fn (alkenyl) Fn (Br) Tb (MPa) Eb (%) 6 317,100 1.16 1.6 0 — — 7 3′ — — — — — — 8 3′ — — — — 0.55 230 Comparative6 17,000 1.13 2.5 — — — Example 6 Comparative 6′ — — — — — — Example 7Comparative 6′ — — — — 0.61 160 Example 8*Fn (alkenyl): the number of alkenyl groups per polymer molecule.Fn (Br): the number of termini having no functional groups introducedper polymer molecule.Tb: tensile strength at break.Eb: elongation at break.“—”: Not determined.

According to the method of the present invention, a polymer having aterminal functional group was produced without fail. Table 1 shows thatthe termini having no functional groups adversely affect the heatstability of the resulting polymer. Since the polymers producedaccording to the present invention had functional groups at the termini,the polymers exhibited higher heat stability. Tables 2 and 3 show thatall of the polymers obtained by the method of the present invention hadterminal functional groups. Thus, the cured products made from thesepolymers exhibited satisfactory elongation.

COMPARATIVE EXAMPLE 9

In a 500 ml round bottomed flask equipped with a reflux tube and astirrer, 2.51 g (17.55 mmol) of copper(I) bromide was charged, and thereactor was purged with nitrogen gas. Into the reactor, 33.56 ml ofacetonitrile was supplied and stirred for 30 minutes at 80° C. in an oilbath. Into the reactor, 335.6 ml (2.34 mol) of butyl acrylate and 3.51 g(9.76 mmol) of diethyl 2,5-dibromoadipate were supplied, and the mixturewas stirred for 25 minutes at 80° C. To the resulting mixture, 0.1222 ml(0.59 mmol) of pentamethyldiethylenetriamine was supplied to initiatereaction. One hundred fifty minutes after the initiation of thereaction, 12.9 ml (0.0872 mol) of 1,7-octadiene was supplied, and thestirring was further continued for 360 minutes. A total of 1.22 ml ofpentamethyldiethylenetriamine was supplied 90, 180, and 270 minutesafter the addition of the octadiene.

The reaction mixture was diluted with toluene in a volume three timesgreater than that of the reaction mixture to filter out the solidcomponents. A solution containing an alkenyl-terminated polymer [7] wasobtained as a result.

The polymer [7] had a number-average molecular weight of 30,600 and amolecular weight distribution of 1.28. The average number of alkenylgroups per polymer molecule determined by ¹H-NMR analysis was 2.28.

EXAMPLE 9

In a 500 ml round bottomed flask equipped with a reflux tube and astirrer, 2.51 g (17.55 mmol) of copper(I) bromide was charged, and thereactor was purged with nitrogen gas. Into the reactor, 33.56 ml ofacetonitrile was supplied, and stirring was performed for 30 minutes at80° C. in an oil bath. Into the reactor, 335.6 ml (2.34 mol) of butylacrylate and 3.51 g (9.76 mmol) of diethyl 2,5-dibromoadipate weresupplied, and the mixture was stirred for 25 minutes at 80° C. To theresulting mixture, 0.1222 ml (0.59 mmol) ofpentamethyldiethylenetriamine was supplied to initiate reaction. Onehundred fifty minutes after the initiation of the reaction, the pressureinside the reactor was gradually reduced using a vacuum pump at 80° C.to recover the acetonitrile and unreacting butyl acrylate (the pressurewas ultimately reduced to 5 Torr, i.e., about 666.6 PA). The recoveryunder reduced pressure was continued for 1 hour. After gaschromatographic analysis confirmed ND (no detection) for theacetonitrile in the polymer, 12.9 ml (0.0872 mol) of 1,7-octadiene andacetonitrile in an amount equal to that at the time of polymerizationwere supplied. The stirring was continued for 360 minutes after theaddition of 1,7-octadiene. A total of 1.22 ml ofpentamethyldiethylenetriamine was supplied 90, 180, and 270 minutesafter the addition of the octadiene. The pressure in the reactor wasreduced with a vacuum pump 360 minutes after the addition of1,7-octadiene so as to recover acetonitrile and unreacting1,7-octadiene.

The reaction mixture was diluted with toluene in a volume three timesgreater than that of the reaction mixture to filter out the solidcomponents. A solution containing an alkenyl-terminated polymer [8] wasobtained as a result.

The polymer [8] had a number-average molecular weight of 31,000 and amolecular weight distribution of 1.33. The average number of alkenylgroups per polymer molecule determined by ¹H-NMR analysis was 2.3.

EXAMPLE 10

In a 100 ml round bottomed flask equipped with a reflux tube and astirrer, 0.375 g (2.62 mmol) of copper(I) bromide was charged, and thereactor was purged with nitrogen gas. Into the reactor, 5.0 ml ofacetonitrile recovered in EXAMPLE 9 was supplied, and the mixture wasstirred for 30 minutes at 80° C. in an oil bath. To the resultingmixture, 50 ml (0.349 mol) of butyl acrylate and 0.78 g (2.18 mol) ofdiethyl 2,5-dibromoadipate were supplied, and the stirring was furthercontinued at 80° C. for 25 minutes. To the resulting mixture, 0.0182 ml(0.09 mmol) of pentamethyldiethylenetriamine was supplied to initiatereaction. One hundred fifty minutes after the initiation of thereaction, the pressure in the reactor was reduced using a vacuum pump torecover acetonitrile and unreacting butyl acrylate. The recovery underreduced pressure was continued for 1 hour. After gas chromatographicanalysis confirmed ND (no detection) for the acetonitrile in thepolymer, 11.4 ml a mixed solution of 1,7-octadiene and acetonitrilerecovered in EXAMPLE 9 was supplied, and the stirring was continued for360 minutes. A total of 0.0273 ml of pentamethyldiethylenetriamine wassupplied 90, 180, and 270 minutes after the addition of the mixedsolution of 1,7-octadiene and acetonitrile.

The reaction mixture was diluted with toluene in a volume three timesgreater than that of the reaction mixture to filter out solidcomponents. A solution containing an alkenyl-terminated polymer [9] wasobtained as a result.

The polymer [9] had a number-average molecular weight of 31,200 and amolecular weight distribution of 1.42. The average number of alkenylgroups per polymer molecule determined by ¹H-NMR analysis was 2.6.

EXAMPLES 9 and 10 and COMPARATIVE EXAMPLE 9 show that, according to theproduction method of the present invention, thefunctional-group-introducing agent and the functional-group-introducingsolvent can be recovered and recycled in high yields.

Industrial Applicability

According to the present invention, polymers having various terminalfunctional groups can be easily produced by supplying compounds(functional-group-introducing agents) containing olefins having a lowpolymerizability and various functional groups to various polymerizationsystems of vinyl monomers. Moreover, according to the present invention,functional groups can be reliably introduced into termini of vinylpolymers. Vinyl polymers having one functional group introduced intoeach terminus through a carbon-carbon bond are stable and can be used incurable composition applications.

Furthermore, according to the production method of the presentinvention, the polymerization solvent, the functional-group-introducingagent, and the functional-group-introducing solvent can be recovered andrecycled in high yields.

1. A method for making a vinyl polymer having a terminus to which afunctional-group-introducing agent is added, comprising: supplying thefunctional-group-introducing agent having a low polymerizability and afunctional-group-introducing solvent having a dielectric constant higherthan that of the functional-group-introducing agent to a polymerizationsystem after 80 percent by weight or more of a vinyl monomer is consumedby atom transfer radical polymerization in a polymerization solvent inthe presence of a polymerization initiator and a transition metalcomplex functioning as a polymerization catalyst, wherein 1 to 1,000parts by weight of the functional-group-introducing solvent to 100 partsby weight of the vinyl monomer is supplied.
 2. The method according toclaim 1, wherein the polymerization solvent and the vinyl monomer areremoved by reduced-pressure distillation while the ability for atomtransfer radical polymerization is maintained, the reduced-pressuredistillation being performed after 80 percent by weight or more of thevinyl monomer is consumed and before the functional-group-introducingagent having a low polymerizability and the functional-group-introducingsolvent having a dielectric constant higher than that of thefunctional-group-introducing agent are supplied.
 3. The method accordingto claim 1, wherein the functional-group-introducing agent is a compoundrepresented by general formula (1):

{wherein R³ represents a hydroxyl group, an amino group, an epoxy group,a carboxylic acid group, an ester group, an ether group, an amido group,a silyl group, a group represented by general formula (2):

(wherein R⁴ represents a hydrogen atom or a methyl group), or a C₁-C₂₀organic group; R¹ represents a C₁-C₂₀ alkylene group or a grouprepresented by general formula (3):

(wherein R⁵ is a C₁-C₂₀ organic group which may contain an oxygen atomor a nitrogen atom; and R⁶s each represent a hydrogen atom or a methylgroup and may be the same or different); and R² represents a hydrogenatom or a methyl group}.
 4. The method according to claim 1, wherein thefunctional-group-introducing agent is a compound represented by generalformula (4):

{wherein R¹ represents a C₁-C₂₀ alkylene group or a group represented bygeneral formula (3):

(wherein R⁵ is a C₁-C₂₀ organic group which may contain an oxygen atomor a nitrogen atom; and R⁶s each represent a hydrogen atom or a methylgroup and may be the same or different); and R² and R⁴ each represent ahydrogen atom or a methyl group}.
 5. The method according to claim 1,wherein the functional-group-introducing agent is a compound representedby general formula (5):

(wherein n is an integer between 1 and 20).
 6. The method according toclaim 1, wherein the functional-group-introducing agent is1,5-hexadiene, 1,7-octadiene, or 1,9-decadiene.
 7. The method accordingto claim 1, wherein R³ in general formula (1) is selected from ahydroxyl group, an amino group, an epoxy group, a carboxylic acid group,an ester group, an ether group, an amido group, and a silyl group. 8.The method according to claim 1, wherein an excess amount of thefunctional-group-introducing agent relative to the propagating terminiof the polymer is supplied.
 9. The method according to claim 1, whereinthe dielectric constant of the functional-group-introducing solvent isat least 3 higher than the dielectric constant of thefunctional-group-introducing agent.
 10. The method according to claim 1,wherein the functional-group-introducing solvent is a nitrile compound.11. The method according to claim 1, wherein 1 to 10,000 parts by weightof the functional-group-introducing solvent to 100 parts by weight ofthe functional-group-introducing agent is supplied.
 12. The methodaccording to claim 1, wherein the vinyl polymer is a (meth)acrylicpolymer.
 13. The method according to claim 1, wherein the number-averagemolecular weight of the vinyl polymer is 500 to 100,000.
 14. The methodaccording to claim 1, wherein the molecular weight distribution of thevinyl polymer is less than 1.8.
 15. The method according to claim 1,wherein the central metal of the transition metal complex is a GroupVIII, IX, X or XI element in the periodic table.
 16. The methodaccording to claim 1, wherein the ligand of the transition metal complexis a polyamine compound.
 17. The method according to claim 1, whereinthe polymerization initiator is a functional-group-containingorganohalide compound or a functional-group-containing sulfonyl halidecompound.
 18. The method according to claim 1, wherein thepolymerization initiator is a polyfunctional initiator.
 19. The methodaccording to claim 2, wherein the polymerization solvent and the monomerremoved by the reduced-pressure distillation are recovered and reused asa polymerization solvent and a monomer.
 20. The method according toclaim 1, wherein the functional-group-introducing agent or a mixture ofthe functional-group-introducing agent and thefunctional-group-introducing solvent is removed by reduced-pressuredistillation after the functional group is bound to a terminus of thevinyl polymer by supplying the functional-group-introducing agent. 21.The method according to claim 20, wherein thefunctional-group-introducing agent or the mixture of thefunctional-group-introducing agent and the functional-group-introducingsolvent removed by the reduced-pressure distillation is recovered andreused as a functional-group-introducing agent or a mixture of afunctional-group-introducing agent and a functional-group-introducingsolvent.
 22. A polymer produced by the method of claim
 1. 23. A curablecomposition comprising the polymer according to claim 22.